CN108137630A - It is fluorinated the prodrug of acyclic nucleoside phosphate ester - Google Patents

Abstract

The present invention relates to novel aminophosphonate prodrugs of acyclic nucleoside phosphonates having a 3-fluoro-2-(phosphonomethoxy)propyl side chain. The present invention also relates to the use of these novel phosphonate-modified nucleosides for the treatment or prevention of viral infections and their manufacture for the treatment or prevention of viral infections, in particular such as hepatitis B virus, human immunodeficiency virus, human cytomegalovirus Use of medicines for viral infections with varicella zoster virus.

Description

Prodrugs of Fluorinated Acyclic Nucleoside Phosphonates

technical field

The present invention relates to novel phosphonoamidate prodrugs of acyclic nucleoside phosphonates having a 3-fluoro-2-(phosphonomethoxy)propyl side chain. The present invention also relates to the use of these novel phosphonate-modified nucleosides for the treatment or prevention of viral infections and their use in the manufacture of medicaments for the treatment or prevention of viral infections, especially those produced by viruses such as hepatitis B virus, human immunodeficiency virus, Infection with human cytomegalovirus and varicella-zoster virus.

Background technique

Acyclic nucleoside phosphonate (ANP) is an important class of antiviral drugs. Their main structural features are: (1) the aliphatic side chain in place of the cyclic sugar moiety and (2) the presence of a phosphonate group attached to the acyclic nucleoside moiety.

The phosphonomethoxy functional group (P-C-O) present in ANP can be considered an isostere of the naturally occurring phosphonic acid-oxymethyl (P-O-C) moiety in nucleoside monophosphonates. In contrast to phosphate groups, phosphonate esters are not susceptible to hydrolysis by phosphonatediesterases and phosphatases and are therefore enzymatically stable. The success of this motif is due to the fact that it is isopolar and isosteric to the phosphate group. Thus, they can undergo enzymatic phosphorylation, which converts them into the corresponding diphosphate phosphonates, which serve as analogs of natural nucleoside triphosphates. Since this phosphonate moiety is a phosphate mimetic group, ANPs require only two (rather than three for regular nucleoside analogs) phosphorylation steps to reach their biologically active phase. This is advantageous because first phosphorylation is often inefficient and rate-limiting in the formation of nucleoside triphosphates. The flexibility in the acyclic sugar side chain allows these compounds to adopt a conformation suitable for interaction with the active site of DNA polymerase or reverse transcriptase upon dephosphorylation.

Extensive studies on the synthesis and antiviral evaluation of ANPs have led to the sale of three ANPs (Figure 1). Cidofovir (HPMPC, (S)-1-(3-hydroxy-2-phosphonomethoxypropyl)cytosine) was approved for the treatment of CMV retinitis in AIDS patients. Adefovir (PMEA, 9-(2-phosphonomethoxyethyl)adenine) is licensed for the treatment of patients with hepatitis B virus infection, and tenofovir (PMPA, (R)-9- (2-phosphonomethoxypropyl)adenine) is used as an anti-HIV and anti-HBV drug. The latter two are marketed as orally bioavailable prodrugs.

The introduction of fluorine atoms into bioactive molecules often results in significant changes in their physical, biological and pharmacokinetic properties. ANPs with fluorinated side chains have been synthesized and tested for antiviral activity. The best studied class of fluorinated ANPs are the 3-fluoro-2-(phosphonomethoxy)propyl (FPMP) derivatives. Both enantiomers of FPMPA and FPMPG (Figure 2) had absolutely no antiviral activity against a broad range of DNA viruses (HSV-1, HSV-2, CMV, VZV, VV). On the other hand, (S)-FPMPA showed potent and selective antiviral activity against HIV-1 and HIV-2 with EC ₅₀ values in the range of 8 μM. The corresponding (R)-FPMPA completely lacks anti-HIV activity (Antimicrob. Agents Chemother. 1993, 37, 332-338). For the guanosine-containing congener (FPMPG), both enantiomers were equally active against HIV-1 and HIV-2, with _EC50 values for both isomers in the range of 5 [mu]M. In addition, nucleobase-modified FPMP derivatives have been synthesized and evaluated for antiviral activity. The diaminopurine congener (FPMPDAP) showed no activity against a panel of DNA viruses, while (R)-FPMPDAP showed _EC50 values of 4.3 μM and 4.6 μM against HIV-1 and HIV-2, respectively.

Phosphonates are negatively charged at physiological pH, and thus cannot penetrate lipid-rich cell membranes, which hinders their antiviral activity. Various prodrug or "pronucleotide" approaches have been investigated to facilitate passive diffusion through lipophilic cell membranes and release the parent nucleotide intracellularly, where it can be further phosphorylated into the pharmacologically active species.

The present invention is based on the unexpected discovery that aminophosphonate prodrugs of fluorinated ANP with a 3-fluoro-2-(phosphonomethoxy)propyl (FPMP) side chain exhibit unexpected biological properties, In particular, it has significant antiviral activity against hepatitis B virus, human immunodeficiency virus, human cytomegalovirus and varicella-zoster virus.

Contents of the invention

The present invention relates to novel aminophosphonate and diaminophosphonate prodrugs of acyclic nucleoside phosphonates (ANPs) and their use as agents for the treatment of viral diseases. It is based on the unexpected discovery that certain nucleoside prodrugs display unexpected biological properties, notably significant activity against hepatitis B virus, human immunodeficiency virus, human cytomegalovirus, and varicella-zoster virus.

The numbered declaration items of the present invention are as follows:

1. A compound of formula I:

in

-B is any natural or modified nucleobase

-R ¹ has the general formula II

in

-R ³ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ -cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) A group consisting of alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl;

-R ⁴ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl, alkoxyalkyl, X-COOR ⁵ , The group consisting of XO(C=O)-R ⁵ ;

wherein X is aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl or C ₃ -C ₈ -cycloalkyl, and wherein said aryl , heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, C ₃ -C ₈ -cycloalkyl optionally contain one or more independently selected from Functional groups, atoms or radicals of the group consisting of halogen, haloalkyl, cyano, C ₁ -C ₇ alkoxy; and

wherein R ⁵ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) group consisting of C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl;

^-R2 is O-Ar, where Ar is a fused bicyclic aryl moiety or a monocyclic aryl moiety, either of which is carbocyclic or heterocyclic and is optionally replaced by halogen, _C1 - _C6 alkane Base, C ₁ -C ₆ alkoxy substitution;

or ^R2 has the general formula II

Wherein R ¹ and R ² can be the same or different;

And/or its pharmaceutically acceptable addition salt and/or its stereoisomer and/or its solvate.

2. The compound according to claim 1, wherein B is selected from the group consisting of adenine, thymine, cytosine and guanine.

3. Compounds according to claim 1 or 2, wherein R ² is O-Ph.

4. The compound according to any one of claims 1 to 3, wherein R ³ is selected from C ₁ -C ₁₀ alkyl.

5. A compound according to any one of claims 1 to 4, wherein R ⁴ is X-COOR ⁵ and wherein X is aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl or C ₃ -C ₈ -cycloalkyl, and wherein said aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ Alkynyl, C ₃ -C ₈ -cycloalkyl optionally contains one or more functional groups, atoms or radicals independently selected from the group consisting of halogen, haloalkyl, cyano, C ₁ -C ₇ alkoxy and wherein R ⁵ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ - The group consisting of C ₆ ) alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl.

6. The compound according to any one of statements 1 to 5, wherein X is C _1- C ₁₀ alkyl and R ⁵ is C _1- C ₁₀ alkyl.

7. The compound according to any one of statements 1 to 6, wherein R ² is O-Ph and wherein R ¹ is

8. A compound selected from the group consisting of: (S)-1-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propane Base}thymine; (R)-1-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}thymine; ( S)-9-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}adenine; (R)-9-{ 3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}adenine; (S)-1-{3-fluoro-2- [Phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}cytosine; (R)-1-{3-fluoro-2-[phenyloxy- Bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}cytosine; (S)-9-{3-fluoro-2-[phenyloxy-bis(pentyl-L -aspartyl)phosphoryl]methoxy]propyl}guanine; (R)-9-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl) Phosphoryl]methoxy]propyl}guanine; (S)-O ² -{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy base]propyl}cytosine; (R)-O ² -{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl} Cytosine; dipentyl ((((R)-1-(2-amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d]pyrimidin-7-yl) -3-fluoropropan-2-yl)oxy)methyl)(phenoxy)phosphoryl)-L-aspartate (dipentyl(((((R)-1-(2-amino -4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-fluoropropan-2-yl)oxy)methyl)(phenoxy )phosphoryl)-L-aspartate, Diamyl(((((R)-1-(2-amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d]pyrimidin -7-yl)-3-fluoro ropropan-2-yl)oxy)methyl)(phenoxy)phosphoryl)-L-aspartate); tetrapentyl 2,2'-((((((R)-1-( 2-Amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-fluoropropan-2-yl)oxy)methyl)phosphonium Acyl)bis(azanediyl))(2S,2'S)-hydrogen succinate (tetrapentyl 2,2'-((((((R)-1-(2-amino-4-oxo -3,4-Dihydro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-fluoropropan-2-yl)oxy)methyl)phosphoryl)bis(azanediyl ))(2S,2' S)-Succinate, Tetraamyl2,2'-((((((R)-1-(2-amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d] pyrimidin-7-yl)-3-fluoropropan-2-yl)oxy)methyl)phosphoryl)bis(azanediyl))(2S,2'S)-disuccinate e).

9. A compound according to any one of claims 1 to 8, for use as a medicament.

10. The use of a compound according to any one of claims 1 to 8 as a medicament for the prophylaxis or treatment of viral infections in animals, mammals or humans.

11. The compound according to claim 10, wherein the viral infection is hepatitis B virus (HBV) infection, human immunodeficiency virus (HIV) infection, varicella zoster virus (VZV) infection, cytomegalovirus (CMV) infection, vaccinia Viral (VV) infection, herpes simplex virus (HSV) infection, BK virus infection, Epstein-Barr virus (EBV) infection, papillomavirus infection, monkeypox virus infection, vaccinia virus infection, hepatitis C virus (HCV) ) infection, respiratory syncytial virus (RSV) infection, dengue virus infection, influenza virus infection, adenovirus infection, parainfluenza virus infection and/or rhinovirus infection.

12. A compound according to any one of claims 1 to 8, for use as a medicament for the prophylaxis or treatment of proliferative diseases such as cancer in animals, mammals or humans.

13. A pharmaceutical composition comprising a therapeutically effective amount of a compound according to any one of claims 1 to 8 and one or more pharmaceutically acceptable excipients.

14. The pharmaceutical composition according to claim 13, further comprising one or more bioactive drugs selected from antiviral drugs and/or antiproliferative drugs.

15. A method of preventing or treating viral infection in animals, mammals or humans, comprising administering a therapeutically effective amount of a compound according to any one of claims 1 to 8, optionally in combination with one or more pharmaceutical agents acceptable excipients.

16. A method of preventing or treating proliferative diseases in animals, mammals or humans, comprising administering a therapeutically effective amount of a compound according to any one of claims 1 to 8, optionally in combination with one or more Pharmaceutically acceptable excipients.

The present invention will now be further described. In the following paragraphs, different aspects of the invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects, unless expressly stated to the contrary. In particular, any feature indicated as preferred or advantageous may be combined with any other feature or features indicated as preferred or advantageous.

Detailed ways

Scheme 1 schematically shows the method for the synthesis of acyclic fluorinated phosphonate 4a/b, which is used to prepare ANP with 3-fluoro-2-(phosphonomethoxy)propyl side chain Important structural units (building blocks). They were prepared according to modified literature reports (Baszczynski, O.; Jansa, P.; Dracinsky, M.; Klepetarova, B.; Holy, A.; Votruba, I.; Clerck, E, D.; Balzarini, J.; Janeba, Z. Bioorg. Med. Chem. 2011, 19, 2114-2124), starting from the commercially available enantiomer O-tritylated glycidol 1a/b and using tosyloxymethyl Diethyl phosphonate instead of diisopropyl tosyloxymethyl phosphonate 1.

Reagents and conditions: (a) KHF ₂ , PhCl, catalyst (cat.) Bu ₄ NH ₂ F ₃ , 135°C, 15h; (b) diethyl tosyloxymethylphosphonate, NaH, THF, 0 ℃ to room temperature, 5h; (c) 80% AcOH, 90℃, 1h.

Scheme 1: Synthesis of (S)/(R)-fluorinated phosphonates 4a/b.

Scheme 2 shows a method for the synthesis of 3-fluoro-2-(phosphonomethoxy)propyl ANP using thymidine as the nucleobase. Condensation of 4a/b with ^N3 -Bom-thymine provided compound 6a/b in high yield. Removal of the ^N3 -Bom group by catalytic hydrogenation using 10% palladium on carbon provided compound 7a/b, followed by hydrolysis of the diester group with TMSBr in dry acetonitrile overnight to form the corresponding phosphonate acid 8a/b.

Reagents and conditions: (a) Ph ₃ P, DIAD, THF, room temperature, 12h; (b) Pd/C, H ₂ , EtOH, room temperature, 24h; (c) TMSBr, 2,6-lutidine, CH ₃ CN, room temperature, 12h.

Scheme 2: Synthesis of (S)/(R)-acyclic fluorinated thymidine phosphonate acid 8a/8b

Scheme 3 shows a method for the synthesis of 3-fluoro-2-(phosphonomethoxy)propyl ANP using adenine as the nucleobase. The Mitsunobu reaction in the presence of 6-chloropurine proceeded smoothly, and compounds 10a/b were obtained in yields of 60% and 65%, respectively. Chloropurines were then partially converted to adenines by treatment with _NH3 in EtOH under pressure, and finally the phosphonate was cleaved with TMSBr to obtain compounds 12a/b in 65% and 70% yields, respectively.

Reagents and conditions: (a) Ph ₃ P, DIAD, THF, room temperature, 12h; (b) NH ₃ /EtOH, 50°C, 24h; (c) TMSBr, 2,6-lutidine, CH ₃ CN, Room temperature, 12h.

Scheme 3: Synthesis of (S)/(R)-acyclic fluorinated adenine phosphonate acids 12a/12b.

Scheme 4 shows a method for the synthesis of 3-fluoro-2-(phosphonomethoxy)propyl ANP using cytosine as the nucleobase. Moderate yields and unexpected formation of O-2-alkylated products 15a/b (ratio 1:1, O-2:N-1 alkylation) were obtained with ^N4 -isobutyrylcytosine. Compounds ^17a /b and 19a/b were obtained after removal of the N4-isobutyryl protecting group and cleavage of the phosphonate in _NH3 /MeOH.

Reagents and conditions: (a) Ph ₃ P, DIAD, THF, room temperature, 12h; (b) NH ₃ /MeOH, 45°C, 15h; (c) TMSBr, 2,6-lutidine, CH ₃ CN, Room temperature, 12h.

Scheme 4: Synthesis of (S)/(R)-acyclic fluorinated cytosine and ^O2 -cytosine phosphonate acids 17a/b and 19a/b.

Scheme 5 shows a method for the synthesis of 3-fluoro-2-(phosphonomethoxy)propyl ANP using guanosine as the nucleobase. The reaction between 6-O-benzylguanine 20 and compound 4a/b yields a mixture of compound 21a/b and the corresponding triphenylphosphine adduct (not shown). The crude mixture residue was then refluxed in THF/ _H2O for several hours to remove the undesired triphenylphosphine adduct. Sequential removal of the 6-O-benzyl protecting group using 10% palladium on carbon and treatment with TMSBr gave the desired product.

Reagents and conditions: (a) Ph ₃ P, DIAD, THF, room temperature, 12h; (b) Pd/C, H ₂ , EtOAc, 10h.; (c) TMSBr, 2,6-lutidine, CH ₃ CN, room temperature, 12h.

Scheme 5: Synthesis of (S)/(R)-acyclic fluorinated guanine phosphonate acids 23a/b.

Schemes 6 and 7 illustrate the conversion of free phosphonic acids to the corresponding aryloxyamino phosphonates. Amino phosphonates 24a/b-27a/b were successfully obtained from 2,2'-dithiobipyridine and triphenylphosphine overnight in pyridine in the presence of triethylamine. However, for the synthesis of guanine aminophosphonates 29a/b, only the unexpected triphenylphosphine adduct 28a/b was formed (Scheme 7). In the case of adenine and cytosine, only small amounts of triphenylphosphine adducts are formed. These triphenylphosphine adducts can be successfully cleaved by treatment with 1M HCl at room temperature.

Reagents and conditions: (a) L-pentanediyl-aspartate HCl salt, PhOH, 2,2'-dithiobipyridine, PPh ₃ , Et ₃ N, pyridine, 60°C, 12h.

Scheme 6: Synthesis of (S)/(R)-acyclic fluorinated nucleoside aminophosphonates 24a/b-27a/b.

Reagents and conditions: (a) L-pentanediyl-aspartate HCl salt, PhOH, 2,2'-dithiodipyridine, PPh ₃ , Et ₃ N, pyridine, 60°C, 12h; (b) 1M HCl, 0°C to room temperature, 1h.

Scheme 7: Synthesis of (S)/(R)-acyclic fluorinated guanine aminophosphonates 29a/b.

Scheme 8 shows a method for the synthesis of 3-fluoro-2-(phosphonomethoxy)propyl ANP using 2-amino-6-(4-methoxy-thiophenol)purine as the nucleobase. Under Mitsunobu reaction conditions (Ph ₃ P, DIAD), 2-amino-6-chloropurine 30 was condensed with precursor 4a/b to give compound 31a/b with concomitant formation of the corresponding triphenylphosphine adduct. These adducts were successfully decomposed by refluxing the crude reaction mixture for 24 hours. Compound 31a/b was heated with 4-methoxythiophenol in DMF in the presence of triethylamine to afford 32a/b in 87% and 67% yield, respectively. Lewis acid-mediated phosphonate deprotection affords compounds 33a/b.

Reagents and conditions: (a) (i) Ph ₃ P, DIAD, THF, room temperature, 24h; (ii) THF/H ₂ O, reflux, 24h; (b) Et ₃ N, DMF, 100°C, 4h; ( c) TMSBr, 2,6-lutidine, CH ₃ CN, room temperature, 12h.

Scheme 8: Synthesis of (R)/(S)-fluorinated acyclic phosphonates 33a/b.

Scheme 9 shows a method for the synthesis of 3-fluoro-2-(phosphonomethoxy)propyl ANP with 7-deazaguanine and 7-deaza-7-fluoro-guanine as nucleobases. Preparation of 4-chloro-5-fluoro-2-pivaloylamino-7H-pyrrolo[2,3-d]pyrimidine 35 starting from commercially available 30. Select fluorine reagents (Selectfluor) as fluorinating reagents following literature protocols (see la, F.; Xu, K.; Chittepu, P. Fluorinated pyrrolo[2,3-d]pyrimidine nucleosides: 7-fluoro- 7-deazapurine 2'-deoxyribofuranoside and 2'-deoxy-2'-fluoroarabinofuran derivatives. Synthesis 2006, 12, 2005-2012). Diethyl phosphonates 36a/b and 37a/b were prepared using standard Mitsunobu conditions ( _Ph3P , DIAD). Sequential replacement of chlorine with hydroxyl and deprotection of pivaloyl were achieved by DABCO/K ₂ CO ₃ and NH ₃ /MeOH, respectively, to afford compounds 38a/b and 39a/b. Hydrolysis of the phosphonate group yields compounds 40a/b and 41a/b.

Reagents and conditions: (a) PivCl, pyridine, room temperature, 3h; (b) selective fluorine reagent, MeCN, 50°C, 30 minutes. (c) Ph ₃ P, DIAD, THF, room temperature, 24h; (d) (i) DABCO, K ₂ CO ₃ , dioxane/H ₂ O, 90°C, 3h; (ii) NH ₃ /MeOH, Room temperature, 12h; (e) TMSBr, 2,6-lutidine, CH ₃ CN, room temperature, 12h.

Scheme 9: Synthesis of (R)/(S)-fluorinated acyclic phosphonates 40a/b and 41a/b.

Scheme 10 shows a method for the synthesis of 3-fluoro-2-(phosphonomethoxy)propyl ANP using 7-deaza-7-cyano-guanine as the nucleobase. Synthesis of heterocyclic building block 46 initiated by formylation of chloroacetonitrile 42 with methyl formate (Llona-Minguez, S.; Mackay, S. P. Stereoselective synthesis of carbocyclic analogues of nucleoside Q precursors (PreQ0). Beilstein J .Org.Chem.2014, 10, 1333-1338). The resulting unstable chloral 43 was used immediately in the next step without further purification to afford the cyclocondensed compound 44. The exocyclic amine was then protected as pivaloyl, and the subsequent chlorination step was accomplished using _POCl3 in the presence of a phase transfer catalyst to provide the desired chloro intermediate 46. Alkylation of 4a/b with 46 was successfully performed by treatment with _Ph3P and DIAD to give compound 47a/b. Since the conversion of 4-chloro to 4-oxo using DABCO/K ₂ CO ₃ was obtained in low yields for 48a, an alternative method by treatment with DABCO/NaOAc was applied on 47b (Brückl, T.; Klepper, F.; Gutsmiedl, K.; Carell, TA short and efficient synthesis of thetRNA nucleosides PreQ0 and archaeosine. Org. Biomol. Chem. 2007, 5, 3821-3825). Thus, the desired product 48b was isolated in good yield (60% over two steps). Finally, cleavage of the phosphonate affords compounds 49a/b.

Reagents and conditions: (a) methyl formate, NaH, THF, 0°C, 5h; (b) 2,6-diamino-6-hydroxypyrimidine, NaOAc, H ₂ O, 100°C, 24h; (c) PivCl , pyridine, 85°C, 2h; (d) POCl ₃ , DMA, BnEt ₃ NCl, MeCN, 90°C, 1h. (e) Ph ₃ P, DIAD, THF, room temperature, 24h; (f) (i) DABCO, K ₂ CO ₃ , dioxane/H ₂ O, 90°C, 3h or DABCO, NaOAc, DMF, room temperature, 48h; (ii) NH ₃ /MeOH, room temperature, 12h; (g) TMSBr, 2,6- Lutidine, CH ₃ CN, room temperature, 12h.

Scheme 10: Synthesis of (R)/(S)-fluorinated acyclic phosphonates 49a/b.

Scheme 11 shows the synthesis of aryloxyaminophosphonate prodrug 50 and bisaminophosphonate prodrug 51 from the corresponding free phosphonic acid 40a. Compound 51 was prepared from the parent phosphonic acid nucleoside 40a using 2,2'-dithiobipyridine and triphenylphosphine as activators and using a mixture of phenol and the appropriate amino acid ester. In a similar manner, the bisaminophosphonate prodrug 51 was prepared using the desired amino acid ester.

Reagents and conditions: (a) for 50, L-aspartic acid pentadecyl ester HCl salt, PhOH, 2,2'-dithiodipyridine, PPh ₃ , Et ₃ N, pyridine, 60°C, 12h; for 51, L-pentamethylene glycol aspartate HCl salt, 2,2'-dithiodipyridine, PPh ₃ , Et ₃ N, pyridine, 60°C, 12h.

Scheme 11: Synthesis of (R)-fluorinated acyclic aminophosphonates 50 and 51

According to one embodiment, the present invention includes compounds of general formula I:

in

-B is any natural or modified nucleobase

-R ¹ has the general formula II

in

-R ³ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ -cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) A group consisting of alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl;

-R ⁴ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl, alkoxyalkyl, X-COOR ⁵ , The group consisting of XO(C=O)-R ⁵ ;

wherein X is aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl or C ₃ -C ₈ -cycloalkyl, and wherein said aryl , heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, C ₃ -C ₈ -cycloalkyl optionally contain one or more independently selected from Functional groups, atoms or radicals of the group consisting of halogen, haloalkyl, cyano, C ₁ -C ₇ alkoxy; and

wherein R ⁵ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) group consisting of C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl;

^-R2 is O-Ar, where Ar is a fused bicyclic aryl moiety or a monocyclic aryl moiety, either of which is carbocyclic or heterocyclic and is optionally replaced by halogen, _C1 - _C6 alkane Base, C ₁ -C ₆ alkoxy substitution;

or ^R2 has the general formula II

Wherein R ¹ and R ² can be the same or different;

And/or its pharmaceutically acceptable addition salt and/or its stereoisomer and/or its solvate.

The base (B) is selected from the group of pyrimidine and purine bases. Such bases include natural bases such as adenine, thymine, cytosine, uracil, guanine and modified bases or modifications of said natural bases. In certain embodiments of the invention, the base is guanine, cytosine, adenine, thymine, cytosine or uracil. In a more specific embodiment of the invention said base is adenine or guanine. In another specific embodiment of the invention, said base is cytosine. In another specific embodiment of the invention, said base is thymine. In another specific embodiment of the invention, said base is uracil. In certain embodiments of the invention, said base is linked to the rest of the compound through its nitrogen atom, for example in Example 31, 32, 33, 34, 35, 36, 39, 40, 67 and 68. In other embodiments of the invention, the base is linked to the rest of the compound through an oxygen atom, such as in Examples 37 and 38. In a more specific embodiment thereof, said base (attached via its oxygen atom to the remainder of formula I) is selected from the list consisting of:

wherein R is selected from the group consisting of H, halogen and methyl. In a more specific embodiment thereof, said base is

Such embodiments thus include compounds of formula Ib:

wherein R ¹ and R ² can have any value as described herein.

In another embodiment, the invention relates to compounds according to the invention, including compounds of formula I, Ib, or any subgroup thereof, wherein Ar is a fused bicyclic aryl moiety or a monocyclic aryl moiety, any of which is The radical moiety is carbocyclic or heterocyclic and is optionally substituted by halogen, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy. In a more specific embodiment, said Ar is phenyl. In particular embodiments of the invention, compounds of formula I, Ib, or any subgroup thereof, may have any value for R ¹ described herein, wherein Ar is phenyl.

In a more specific embodiment, said R ³ is C ₁ -C ₁₀ alkyl. In another specific embodiment, said R ³ is C ₃ -C ₁₀ alkyl. In another specific embodiment, said R ³ is C ₁ -C ₅ alkyl. In another specific embodiment, said R ³ is C ₃ -C ₅ alkyl. In another specific embodiment, said R ³ is C ₅ alkyl.

In another specific embodiment, said R ⁴ is selected from the group consisting of C ₁ -C ₁₀ alkyl or X-COOR ⁵ , wherein R ⁵ may have any value as described herein. In a more specific embodiment, said R ⁵ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl , aryl(C ₁ -C ₆ )alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxy group consisting of alkyl groups. In more specific embodiments, R ⁵ is C _1- C ₇ alkyl or C _3- C ₈ cycloalkyl; in more specific embodiments, R ⁵ is C _1- C ₅ alkyl, and in another In a more specific embodiment, R ⁵ is C _{3 -C 7} alkyl, and in an even more specific embodiment, R ⁵ is C _{3 -C 5} alkyl. In a more specific embodiment, R ⁵ is C ₅ alkyl. In another specific embodiment, R ⁵ is aryl-(C ₁ -C ₂ )alkyl; in another more specific embodiment, R ⁵ is benzyl or phenyl-methyl.

In another specific embodiment, X is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl or C ₃ -C ₈ -cyclic The group consisting of alkyl, and wherein said aryl, heteroaryl, C ₁ -C ₁₀ alkyl and C ₃ -C ₈ -cycloalkyl optionally contain one or more independently selected from halogen, carbonyl, Thiocarbonyl, hydroxyl, thiol, ether, thioether, acetal, thioacetal, amino, imino, oxime, alkyloxime, amino acid, cyano, acylamino, thioacylamino, carbamoyl , thiocarbamoyl, urea, thiourea, carboxylate or halide or anhydride or amide, thiocarboxylic acid or ester or thioester or halide or anhydride or amide, nitro, thio C _{1- 7} Alkyl, Thio C _{3 -} C ₁₀ Cycloalkyl, Hydroxyamino, Mercaptoamino, Alkyl-amino, Cycloalkylamino, Alkenylamino, Cycloalkenylamino, Alkynylamino, Arylamino, Aryl Alkylamino, hydroxyalkylamino, mercaptoalkylamino, heterocyclic substituted alkylamino, heterocyclic amino, heterocyclic substituted arylamino, hydrazine, alkylhydrazino, phenylhydrazino, sulfonyl, substituent A functional group, atom or free radical of the group consisting of sulfonyl and sulfonamide. In a more specific embodiment, X is selected from the group consisting of aryl, heteroaryl, C ₁ -C ₁₀ alkyl or C ₃ -C ₈ -cycloalkyl, more specifically said X is C ₁ -C ₆ alkyl, even more specifically said X is C ₁ -C ₃ alkyl or C ₁ -C ₂ alkyl or -CH ₂ -.

Particular novel compounds according to the invention include the individual compounds the preparation of which is described in the appended examples and their pharmaceutically acceptable salts and solvates.

The present invention also relates to compounds of formula I, Ib or any subgroup thereof or stereoisomeric forms thereof for use as a medicament.

The present invention also relates to compounds of formula I, Ib or any subgroup thereof or stereoisomeric forms thereof for use as a medicament for the prophylaxis or treatment of viral and neoplastic diseases in animals, preferably mammals. In one embodiment, the disease is a viral disease, including diseases caused by viral infections, such as those caused by HBV, HIV, HCV, RSV, dengue virus, influenza virus, VZV, CMV, adenovirus, parainfluenza virus, nasal Infection by viruses, BK virus and/or HSV; In another embodiment, the disease is a neoplastic disease, which may be acute or chronic, including proliferative diseases, especially cancer. In one embodiment, the mammal is a human. In a particular embodiment, said compound for use as a medicament, in particular for the prophylaxis or treatment of viral diseases, is a compound of formula I and Ib, including any subgroup thereof. In a more specific embodiment thereof, said compound of formula I has as base B a pyrimidine base, more specifically, a pyrimidine base represented by structural formula (IV):

or

A purine base, more specifically a purine base represented by structural formula (V):

in:

R and ^{R are} independently selected from the group consisting ^of H, -OH, -SH, _-NH and -NH-Me;

R ^{and R} are independently selected from the group consisting of H, methyl, ethyl, isopropyl, hydroxy, amino, ethylamino, trifluoromethyl, cyano, and halogen; and

X ¹ and Y ¹ are independently selected from CR ¹¹ and N, wherein R ¹¹ is selected from the group consisting of H, halogen and cyano.

The present invention also relates to the use of a compound of formula I, Ib or any subgroup thereof or a stereoisomeric form thereof in the preparation of a medicament for the prevention or treatment of viral diseases and/or tumor diseases in animals. In one embodiment, the animal is a mammal, preferably the mammal is a human.

In a further specific embodiment, the viral disease is a disease caused by viral infection, such as HBV, HIV, HCV, RSV, dengue virus, influenza virus, CMV, VZV, adenovirus, parainfluenza virus, rhinovirus , BK virus and/or HSV infection. In an even more specific embodiment, said viral disease is a disease caused by HBV and/or HIV viral infection. In a specific embodiment, the viral disease is a disease caused by HBV virus infection. In another specific embodiment, said viral disease is a disease caused by HIV1 virus infection.

The present invention also relates to a pharmaceutical composition comprising a therapeutically effective amount of a compound of formula I, Ib, or any subgroup thereof, or a stereoisomeric form thereof, and one or more pharmaceutically acceptable excipients. The composition may also contain one or more biologically active drugs selected from antiviral drugs and antitumor drugs.

The present invention also relates to a method of preventing or treating viral diseases in animals, comprising administering a therapeutically effective amount of a compound of formula I, Ib, or any subgroup or stereoisomeric form thereof, optionally in combination with one or more a pharmaceutically acceptable excipient.

The present invention also relates to a method of preventing or treating neoplastic diseases in animals, which comprises administering a therapeutically effective amount of a compound of formula I, Ib or any subgroup thereof or a stereoisomeric form thereof, optionally in combination with one or more a pharmaceutically acceptable excipient.

For use in medicine, salts of compounds of formula I or Ib will be pharmaceutically acceptable salts. However, other salts may be used in the preparation of the compounds of the present invention or their pharmaceutically acceptable salts. Suitable pharmaceutically acceptable salts of the compounds of the present invention include acid addition salts which can be obtained, for example, by mixing a solution of the compound of the present invention with a pharmaceutically acceptable acid such as hydrochloric acid, sulfuric acid, methanesulfonic acid, fumaric acid , maleic acid, succinic acid, acetic acid, benzoic acid, citric acid, tartaric acid or phosphoric acid solution mixed to form. Furthermore, where a compound of the present invention carries an acidic moiety such as a carboxyl group, suitable pharmaceutically acceptable salts thereof may include alkali metal salts, such as sodium or potassium salts; alkaline earth metal salts, such as calcium or magnesium salts; and Salts formed from suitable organic ligands, such as quaternary ammonium salts.

The present invention includes within its scope solvates of the compounds of formulas I and Ib above. Such solvates can be formed with common organic solvents, for example, hydrocarbon solvents such as benzene or toluene; chlorinated solvents such as chloroform or methylene chloride; alcoholic solvents such as methanol, ethanol or isopropanol; ethereal solvents such as diethyl ether or tetrahydrofuran; or Ester solvents such as ethyl acetate. Alternatively, solvates of the compounds of formula I and Ib may be formed with water, in which case they will be hydrates.

The compounds according to the invention are useful in the treatment and/or prophylaxis of various animal, mammalian or human ailments or diseases. These include viral diseases, such as those caused by viral infections, such as those caused by HBV, HIV, HCV, RSV, dengue virus, influenza virus, herpes simplex virus 1 and 2 (HSV-1 and HSV-2), varicella zoster Herpes virus (VZV), Epstein-Barr virus (EBV or HHV-4), human cytomegalovirus (HCMV or HHV-5), human herpesvirus 6A and 6B (HHV-6A and HHV-6B), human herpes Infection with Kaposi's sarcoma-associated herpesvirus 7 (HHV-7) and Kaposi's sarcoma-associated herpesvirus (KSHV, also known as HHV-8), adenovirus, parainfluenza virus, rhinovirus, and/or BK virus; and neoplastic disorders such as proliferative disorders (eg, cancer).

Viral diseases include infections caused by various viral families including Hepadnaviridae, Retroviridae, Herpesviridae, Papillomaviridae, Papillomaviridae or Papillomaviruses, Flaviviridae, Picornaviridae Nucleoviridae. The various genera within the Hepadnaviridae family include the genera Orthodnavirus and Avian Hepadnavirus; members of the Orthodnavirus genus include hepatitis B virus (HBV) and woodchuck hepatitis Virus. Members of the avian hepadnavirus genus include duck hepatitis B virus. The various genera within the Retroviridae family include alpharetroviruses, betaretroviruses, gammaretroviruses, deltaretroviruses, epsilonretroviruses, lentiviruses, and spumaviruses. Members of the lentivirus genus include human immunodeficiency virus 1 (HIV-1 ) and human immunodeficiency virus 2 (HIV-2). The various genera within the family Herpesviridae include (i) those within the subfamilies of the subfamily Alphaherpesvirinae: Varicellavirus, Scutavirus, Throatvirus, Marekvirus, Herpes simplexvirus (ii) within the subfamilies of the subfamily Beta-herpesvirinae: cytomegalovirus, murine cytomegalovirus, Proboscivirus, roseolavirus; and (iii) within the subfamily Gammaherpesvirinae Within the subfamilies of the family: Lymphocyptovirus, Macavirus, Percavirus, Slendervirus. Members of the varicellavirus genus include varicella-zoster virus (VZV); simian herpesvirus; seal herpesvirus type 1; porcine herpesvirus type 1; feline herpesvirus type 1; Deer herpesviruses 1 and 2; Rhesus herpesvirus 9; Caprine herpesvirus 1; Bovine herpesviruses 1 and 5; African oryx herpesvirus 1; Canine herpesvirus 1. Members of the genus Herpes simplexviruses include human herpesviruses 1 and 2. Members of the genus Scutivirus include snake herpesvirus type 5. Members of the laryngopharyngeal virus genus include avian herpesvirus type 1. Members of the Marekvirus genus include avian herpesvirus type 2. Members of the genus Cytomegalovirus include the human cytomegalovirus (CMV). Members of the genus Probosciviridae include herpesvirus type 1. Members of the murine cytomegalovirus genus include murine herpesvirus type 1. Members of the roseolavirus genus include human herpesviruses 6A, 6B, and 7. Members of the Lymphocryptovirus genus include human herpesvirus type 4. Members of the Macavirus genus include harpe herpesvirus type 1. Members of the genus Percavirus include equine herpesvirus type 2. Members of the squirrel virus genus include squirrel monkey herpesvirus type 2, Kaposi's sarcoma-associated virus. The various genera within the family Flaviviridae include flaviviruses, pestiviruses, hepatitis viruses, and hepatitis G viruses. The Papovaviridae family includes polyomaviruses (e.g., JC virus; BK virus; Merkel cell polyomavirus; Trichodysplasia spinulosa polyomavirus; human polyomavirus types 6, 7, and 12; and human polyomavirus 6 , 7, 9 and 12; New Jersey polyomavirus; KI polyomavirus; WU polyomavirus; MW polyomavirus; STL polyomavirus). The papillomaviridae or papillomaviruses include the human papillomavirus (HPV). Members of the Flavivirus genus include dengue virus, yellow fever virus, West Nile encephalitis virus, and Japanese encephalitis virus. Members of the Pestivirus genus include bovine viral diarrhea virus (BVDV), classical swine fever virus, and border disease virus type 2 (BDV-2). Members of the Hepacivirus genus include the hepatitis C virus (HCV). Members of the Hepacivirus genus include Hepatitis G virus. The various genera in the picornaviridae family include Foot-and-Mouth Disease Virus, Avian Hepadovirus, Cardiovirus, Enterovirus, Equine Rhinovirus, Hepavirus, Kobuvirus, Parechovirus, Sapelovirus, Senecavirus, Teschovirus and Tremovirus. Members of the Enterovirus genus include polioviruses, coxsackie A viruses, coxsackie B viruses, and rhinoviruses.

Neoplastic diseases, which may be acute or chronic, include proliferative diseases, especially cancer, in animals including mammals, especially humans. Specific types of cancer include hematological malignancies (including leukemias and lymphomas) and non-hematological malignancies (including solid tumor carcinomas, sarcomas, meningiomas, glioblastoma multiforme, neuroblastoma, melanoma , gastric cancer and renal cell carcinoma). Chronic leukemia can be myeloid or lymphoid. Types of leukemia include lymphoblastic T-cell leukemia, chronic myelogenous leukemia (CML), chronic lymphocytic/lymphoid leukemia (CLL), hairy cell leukemia, acute lymphoblastic leukemia (ALL), acute myelogenous leukemia ( AML), myelodysplastic syndrome, chronic neutrophil leukemia, acute lymphoblastic T-cell leukemia, plasmacytoma, immunoblastic large cell leukemia, mantle cell leukemia, multiple myeloma, acute megakaryocyte Leukemia, acute megakaryoblastic leukemia, promyelocytic leukemia and erythroleukemia. Types of lymphoma include malignant lymphoma, Hodgkin lymphoma, non-Hodgkin lymphoma, lymphoblastic T-cell lymphoma, Burkitt lymphoma, follicular lymphoma, MALT1 lymphoma, and marginal zone lymphoma tumor. Non-hematological malignancies include prostate cancer, lung cancer, breast cancer, rectal cancer, colon cancer, lymph node cancer, bladder cancer, kidney cancer, pancreatic cancer, liver cancer, ovarian cancer, uterine cancer, cervical cancer, brain cancer, skin cancer, bone cancer cancer, stomach cancer and muscle cancer.

The present invention also provides a pharmaceutical composition comprising the compound of the present invention as described above or a pharmaceutically acceptable salt or solvate thereof in combination with one or more pharmaceutically acceptable carriers.

The pharmaceutical compositions according to the invention may take a form suitable for oral, buccal, parenteral, nasal, topical, ophthalmic or rectal administration, or a form suitable for administration by inhalation or insufflation.

The amount of a compound used in the invention required to prevent or treat a particular condition or disease will vary depending on the compound selected and the condition of the animal, mammal or human patient to be treated. In general, however, the daily dosage may range from about 10 ng/kg to 1000 mg/kg, typically 100 ng/kg to 100 mg/kg for oral or buccal administration, for example about 0.01 mg/kg to 40 mg/kg body weight , about 10 ng/kg to 50 mg/kg body weight for parenteral administration, and about 0.05 mg to about 1000 mg, for example about 0.5 mg to about 1000 mg, for nasal administration or administration by inhalation or insufflation.

definition

As used herein, the term "pyrimidine and purine bases" includes, but is not limited to: adenine, thymine, cytosine, uracil, guanine, 2,6-diaminopurine, 5-fluorocytosine, 5-fluorouracil, 7-deazaguanosine, 7-deazaadenine and their analogs. As used herein, a purine or pyrimidine base includes a purine or pyrimidine base as described above found in naturally occurring nucleosides. Its analogues are those that mimic naturally occurring bases in such a way that their structure (atomic species and their arrangement) resembles those of naturally occurring bases, but may have additional or lack some of the functional properties of naturally occurring bases base of base. Such analogs include those obtained by substituting a CH moiety with a nitrogen atom (e.g., 5-azapyrimidines such as 5-azacytosine) or vice versa (e.g., 7-deazapurines, such as 7-deazaadenine or 7-deazaguanine) or both (eg, 7-deaza, 8-deazapurines). Derivatives of such bases or analogs refer to those in which the ring substituents are combined, removed or modified by conventional substituents known in the art, such as halogen, hydroxyl, amino, (C _1- C ₆ ) alkyl, etc. those bases. Such purine or pyrimidine bases and their analogs are well known to those skilled in the art, eg as shown on pages 20-38 of WO 03/093290.

In particular, the purine and pyrimidine analogs B for the purposes of the present invention may be selected from the group comprising pyrimidine bases represented by structural formula (IV):

and a purine base represented by structural formula (V):

in:

R and ^{R are} independently selected from the group consisting ^of H, -OH, -SH, _-NH and -NH-Me;

R ^{and R} are independently selected from the group consisting of H, methyl, ethyl, isopropyl, hydroxy, amino, ethylamino, trifluoromethyl, cyano, and halogen; and

X ¹ and Y ¹ are independently selected from CR ¹¹ and N, wherein R ¹¹ is selected from the group consisting of H, halogen and cyano.

As some non-limiting examples of pyrimidine analogs, can be named as substituted uracils having formula (IV), wherein ^X is CH, R is ^hydroxyl , and ^R is selected from the group consisting of methyl, ethyl, isopropyl The group consisting of radical, amino, ethylamino, trifluoromethyl, cyano, fluorine, chlorine, bromine and iodine.

As used herein, the term "alkyl" refers to a straight (normal) or branched (e.g., secondary or tertiary) hydrocarbon chain having the indicated number of carbon atoms (or where not specified, preferably having 1-20 , more preferably 1-6 carbon atoms). The term "C ₁ -C ₆ alkyl" refers to such hydrocarbon chains having 1 to 6 carbon atoms. Examples are methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-methyl-1-propyl (isobutyl), 2-butyl (sec-butyl) 2- Methyl-2-propyl (tert-butyl), 1-pentyl (n-pentyl), 2-pentyl, 3-pentyl, 2-methyl-2-butyl, 3-methyl-2- Butyl, 3-methyl-1-butyl, 2-methyl-1-butyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-2-pentyl, 3-methyl- 2-pentyl, 4-methyl-2-pentyl, 3-methyl-3-pentyl, 2-methyl-3-pentyl, 2,3-dimethyl-2-butyl, 3, 3-Dimethyl-2-butyl, n-pentyl, n-hexyl.

As used herein with respect to substituents, unless otherwise stated, the term "C ₂ -C ₁₀ alkenyl" refers to straight and branched chains having one or more ethylenic unsaturations and having from 2 to 10 carbon atoms Chain acyclic hydrocarbon monovalent free radicals such as for example vinyl, 1-propenyl, 2-propenyl (allyl), 1-butenyl, 2-butenyl, 2-pentenyl, 3-pentene Base, 3-methyl-2-butenyl, 3-hexenyl, 2-hexenyl, 2-heptenyl, 1,3-butadienyl, pentadienyl, hexadienyl, Heptadienyl, heptatrienyl, 2-octenyl, etc., including all possible isomers thereof.

As used herein with respect to substituents, the term "C ₂ -C ₁₀ alkynyl" defines, unless otherwise stated, a group containing one or more triple bonds and optionally at least one double bond and having 2 to 10 carbon atoms straight-chain and branched-chain hydrocarbon groups, such as ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 2-pentynyl, 1-pentynyl, 3 -Methyl-2-butynyl, 3-hexynyl, 2-hexynyl, 1-penten-4-ynyl, 3-penten-1-ynyl, 1,3-hexadiene- 1-Alkynyl etc.

As used herein and unless otherwise stated, the term "cycloalkyl" refers to a monovalent monocyclic radical of a monocyclic saturated hydrocarbon having the indicated number of carbon atoms (or where not specified, preferably having 3-20, more preferably 3-10 carbon atoms, more preferably 3-8 or 3-6 carbon atoms). "C ₃ -C ₈ cycloalkyl" refers to such a monocyclic saturated hydrocarbon monovalent group having 3 to 8 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, Cyclooctyl.

The term "alkoxy" refers to the group alkyl-O-, wherein alkyl is as defined above. As used herein, "(C ₁ -C ₆ )alkoxy" includes, but is not limited to, methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy , pentyloxy, 3-pentyloxy or hexyloxy.

As used herein and unless otherwise stated, the term "halogen" or "halo" refers to any atom selected from fluorine (F), chlorine (Cl), bromine (Br) and iodine (I).

As used herein and unless otherwise stated, the term "Ar" or "aryl" refers to a monovalent unsaturated aromatic group having 1, 2, 3, 4, 5 or 6 rings, preferably 1, 2 or 3 rings. family of carbocyclic groups, which may be fused or bicyclic. With regard to optional substituents that may be present on the group Ar or on the aryl group, the aryl group may optionally be substituted with one, two, three or more substituents as described herein. Preferred aryl groups are: aromatic monocyclic rings containing 6 carbon atoms; aromatic bicyclic or fused ring systems containing 7, 8, 9 or 10 carbon atoms; or containing 10, 11, 12, 13 or 14 Aromatic tricyclic ring system with carbon atoms. Non-limiting examples of aryl include phenyl and naphthyl. Preferred substituents for Ar are independently selected from halogen, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy, hydroxyl (-OH), acyl (R'-C(=O)-, acyloxy ( R'-C(=O)-O-), nitro (-NO ₂ ), amino (-NH ₂ ), -SO ₃ H, -SH, -SR', wherein R' is an alkyl group. Preferred Ar are phenyl, bromophenyl and naphthyl.

As used herein and unless otherwise stated, the term "stereoisomers" refers to all possible different isomers and conformational forms, in particular all possible stereochemistry and conformational isomers, that compounds of formulas I and Ib may possess Forms, all diastereoisomers, enantiomers and/or conformations of the basic molecular structure. Some of the compounds of the present invention may exist in different tautomeric forms, all of which are included within the scope of the present invention.

As used herein and unless otherwise stated, the term "enantiomer" refers to each individual optically active form of a compound of the invention, either in optical purity or in enantiomeric excess (as determined by standard methods in the art). ) is at least 80% (ie, at least 90% of one enantiomer and at most 10% of the other), preferably at least 90%, and more preferably at least 98%.

Example

Experimental part

For the reactions, all reagents and solvents were purchased from commercial sources and used as received. Moisture-sensitive reactions were performed in oven-dried glassware under nitrogen or argon atmosphere. ¹ H, ¹³ C and ³¹ P NMR spectra were recorded on a Bruker Avance 300, 500 or 600 MHz spectrometer, and ³¹ P NMR experiments were performed using tetramethylsilane as internal standard or reference residual solvent signal, and 85% H ₃ PO ₄ . The intermediates and final compounds were characterized by using 2D NMR (H-COSY, HSQC and HMBC) spectroscopic techniques. High resolution mass spectra (HRMS) were acquired on a quadruple orthogonal acceleration time-of-flight mass spectrometer (Synapt G2HDMS, Waters, Milford, MA). Samples were infused at 3 μL/min and spectra were acquired in positive (or negative) ionization mode at a resolution of 15000 (fwhm) using leucine enkephalin as lock mass. Pre-coated aluminum plates (254 nm) were used for TLC. The product was subjected to silica gel column chromatography ( 0.035-0.070mm, Acros Organics) purification. Preparative RP-HPLC purification was performed on a Phenomenex Gemini 110A column (C18, 10 μm, 21.2 mm×250 mm) using a gradient of H ₂ O/CH ₃ CN containing 50 mmol of TEAB or H ₂ O/CH ₃ CN as the eluent.

Example 1: Synthesis of (S)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-N ³ -(benzyloxymethyl)thymine (6a)

A solution of DIAD (0.32 mL, 1.64 mmol) in anhydrous THF (1 mL) was added dropwise to compound 4a ¹ (200 mg, 0.82 mmol), compound 5 (240 mg, 0.98 mmol) and Ph ₃ P (430 mg, 1.64mmol) in a mixture of anhydrous THF (5mL). The reaction mixture was stirred for 12 hours, then it was concentrated under reduced pressure. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 80:1, v/v; DCM/MeOH, 50:1, v/v) to give 6a (310 mg, 80%) as a colorless oil . ¹ H NMR (300MHz, CDCl ₃ ): δ7.39-7.25 (m, 5H, ArH), 7.14-7.12 (m, 1H, H-6), 5.50 (s, 2H, OCH ₂ N), 4.73-4.33 (m,4H,CH ₂ -Ar,H-3'),4.17-3.92(m,7H,H-1',H-2',2x CH ₂ CH ₃ ),3.84-3.66(m,2H,PCH ₂ ), 1.93 (d, J=1.2Hz, 3H, CH ₃ -5), 1.34-1.28 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ163.8 (C -4), 151.8(C-2), 140.5(C-6), 138.1(Ar-C), 128.3(Ar-C), 127.7(Ar-C), 109.7(C-5), 82.3(d, ¹ J _C,F ＝173.4Hz,C-3'),78.6(dd, ² J _C,F ＝18.5Hz, ³ J _C,P ＝9.8Hz,C-2'),72.3(OCH ₂ N), 70.8 (CH ₂ -Ar), 64.6 (d, ¹ J _{C, P} ＝167.4Hz, CH ₂ P), 62.6, 62.5 (2×d, ² J _{C, P} ＝3.8Hz, CH ₂ CH ₃ ), 62.5 (d, ² J _{C, P} ＝3.7Hz, CH ₂ CH ₃ ), 49.3 (d, ³ J _{C, F} ＝8.6Hz, C-1'), 16.6, 16.5 (CH ₂ CH ₃ ), 13.0 (CH ₃ -5); ³¹ P NMR (121 MHz, CDCl ₃ ): δ 20.8; HRMS calcd for C ₂₁ H ₃₀ FN ₂ O ₇ P[M+H] ⁺ : 473.1847, found: 473.1848.

Example 2: Synthesis of (R)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-N3-(benzyloxymethyl)thymine (6b)

From compound 4b ¹ (300 mg, 1.23 mmol), compound 5 (360 mg, 1.47 mmol), Ph ₃ P (640 mg, 2.46 mmol) and DIAD (0.48 mL, 2.46 mmol) in anhydrous THF according to the procedure used for the preparation of 6a (8 mL) solution started to give compound 6b (460 mg, 70%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 80:1, v/v; DCM/MeOH, 50:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ7.39-7.25 (m, 5H, ArH), 7.13 (t, J=1.3Hz, 1H, H-6), 5.50 (s, 2H, OCH ₂ N), 4.73-4.33(m,4H,CH ₂ -Ar,H-3'),4.17-3.91(m,7H,H-1',H-2',2x CH ₂ CH ₃ ),3.84-3.66(m, 2H, PCH ₂ ), 1.93 (d, J=1.1Hz, 3H, CH ₃ -5), 1.34-1.28 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ163. 8(C-4), 151.8(C-2), 140.5(C-6), 138.0(Ar-C), 128.3(Ar-C), 127.7(Ar-C), 109.7(C-5), 82.3 (d, ¹ J _C,F ＝173.5Hz,C-3'),78.6(dd, ² J _C,F ＝18.5Hz, ³ J _C,P ＝9.7Hz,C-2'),72.3(OCH ₂ N), 70.7(CH ₂ -Ar), 64.6(d, ¹ J _{C, P} ＝167.3Hz, CH ₂ P), 62.6, 62.5(2×d, ² J _{C, P} ＝3.5Hz, CH ₂ CH ₃ ), 49.3(d, ³ J _{C, F} ＝8.8Hz, C-1'), 16.6, 16.5(CH ₂ CH ₃ ), 13.0(CH ₃ -5); ³¹ P NMR(121MHz, CDCl ₃ ): δ20 .8; HRMS calcd for _C21H30FN2O7P [M+H] ⁺ : _473.1847 , _{found :} 473.1841.

Example 3: (S)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}thymine (7a)

A suspension of compound 6a (240 mg, 0.51 mmol) and Pd/C on charcoal (10% w/w, 120 mg) in EtOH (10 mL) was purged with nitrogen and then hydrogen, then allowed to stir under an atmosphere of hydrogen. After 24 hours, the mixture was filtered through a pad of celite, and the filtrate was evaporated under reduced pressure to give the crude product. Then, the residue was redissolved in MeOH (10 mL) and _Et3N (1 mL), and the solution was stirred at room temperature for 3 h. The reaction mixture was concentrated under reduced pressure and the resulting crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 30:1, v/v; DCM/MeOH, 20:1, v/v) to give a colorless oil Form 7a (160 mg, 90%). ¹ H NMR (300MHz, CDCl ₃ ): δ9.63 (s, 1H, NHCO), 7.16 (t, J=1.3Hz, 1H, H-6), 4.72-4.33 (m, 2H, H-3') ,4.17-3.90(m,7H,H-1',H-2',2x CH ₂ CH ₃ ),3.83-3.63(m,2H,PCH ₂ ),1.89(d,J＝1.2Hz,3H,CH ₃ -5), 1.33-1.28 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ164.5 (C-4), 151.3 (C-2), 141.9 (C- 6),110.4(C-5),82.3(d, ¹ J _C,F ＝173.4Hz,C-3'),78.7(dd, ² J _C,F ＝18.5Hz, ³ J _C,P ＝9.5Hz ,C-2'),64.6(d, ¹ J _C,P ＝167.3Hz,CH ₂ P),62.7,62.6(CH ₂ CH ₃ ),48.6(d, ³ J _C,F ＝8.8Hz,C- 1'), 16.6, 16.5(CH ₂ CH ₃ ), 12.3(CH ₃ -5); ³¹ P NMR (121MHz, CDCl ₃ ): δ21.0; HRMS for C ₉ H ₁₄ FN ₂ O ₆ P[M+ H] ⁺ Calculated: 353.1272, Found: 353.1262.

Example 4: Synthesis of (R)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}thymidine (7b).

From compound 6b (400 mg, 0.85 mmol), Pd/C on charcoal (10% w/w, 200 mg) in EtOH (20 mL) and _Et3N (1 mL) in MeOH (20 mL) according to the preparation procedure for 7a From solution, compound 7b (270 mg, 90%) was obtained as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 30:1, v/v; DCM/MeOH, 20:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ9.67 (s, 1H, NHCO), 7.18 (d, J=1.4Hz, 1H, H-6), 4.75-4.35 (m, 2H, H-3') ,4.19-3.93(m,7H,H-1',H-2',2x CH ₂ CH ₃ ),3.86-3.66(m,2H,PCH ₂ ),1.92(d,J＝1.2Hz,3H,CH ₃ -5), 1.35-1.31 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ164.5 (C-4), 151.3 (C-2), 141.9 (C- 6),110.4(C-5),82.3(d, ¹ J _C,F ＝173.4Hz,C-3'),78.7(dd, ² J _C,F ＝18.5Hz, ³ J _C,P ＝9.5Hz ,C-2'),64.6(d, ¹ J _C,P ＝167.4Hz,CH ₂ P),62.7,62.6(2×d, ² J _C,P ＝5.5Hz,CH ₂ CH ₃ ),48.5( d, ³ J _{C, F} ＝8.8Hz, C-1'), 16.6, 16.5 (CH ₂ CH ₃ ), 12.3 (CH ₃ -5); ³¹ P NMR (121MHz, CDCl ₃ ): δ21.0; HRMS _{Calcd .} for _C9H14FN2O6P [M+H] ⁺ : 353.1272, found _: 353.1278.

Example 5: Synthesis of (S)-1-[3-fluoro-2-(phosphonomethoxy)propyl]thymine triethylammonium salt (8a)

Bromotrimethylsilane (0.15mL, 1.14mmol) was added dropwise to diethylphosphonate 7a (100mg, 0.28mmol) and 2,6-lutidine (0.26mL, 2.27mmol) at 0°C ) in anhydrous acetonitrile (5 mL). After the addition was complete, the mixture was slowly warmed to room temperature and left in the dark for 12 hours. The reaction was quenched with 0.1M TEAB, then concentrated under reduced pressure. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH/Et ₃ N, 10:5:1, v/v/v; 7.5:5:1, v/v/v). The collected eluate was repeatedly freeze-dried to constant weight to obtain the desired triethylammonium phosphonate 8a (59 mg, 70%) in the form of white foam. ¹ H NMR (300MHz, D ₂ O): δ7.52(s, 1H, H-6), 4.77-4.48(m, 2H, H-3', overlapping with H ₂ O), 3.93-3.79(m, 3H, H-1', H-2'), 3.58-3.46 (m, 2H, PCH ₂ ), 1.80 (s, 3H, CH ₃ -5); ¹³ C NMR (75MHz, D ₂ O): δ166. 8(C-4), 152.2(C-2), 143.5(C-6), 110.3(C-5), 82.1(d, ¹ J _{C, F} ＝167.3Hz, C-3'), 77.1(dd , ² J _C,F ＝18.1Hz, ³ J _C,P ＝10.4Hz,C-2'),67.7(d, ¹ J _C,P ＝150.9Hz,CH ₂ P),47.3(d, ³ J _{C , F} ＝6.9Hz, C-1'), 11.0 (CH ₃ -5); ³¹ P NMR (121MHz, D ₂ O): δ12.9; HRMS for C ₉ H ₁₄ FN ₂ O ₆ P[MH] ^- Calculated: 295.0501, Found: 295.0499.

Spectral data were in accordance with literature data (Pomeisl, K.; Pohl, R.; Holy, A.; Votruba, I. Collect. Czech. Chem. Commun. 2005, 70, 1465-1481).

Example 6: Synthesis of (R)-1-[3-fluoro-2-(phosphonomethoxy)propyl]thymine triethylammonium salt (8b)

According to the procedure for the preparation of 8a, from compound 7b (300 mg, 0.85 mmol), bromotrimethylsilane (0.45 mL, 3.41 mmol) and 2,6-lutidine (0.79 mL, 6.81 mmol) in anhydrous acetonitrile (10 mL), compound 8b (176 mg, 70%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH/Et ₃ N, 10:5:1, v/v/v; 7.5:5:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ7.55-7.54 (m, 1H, H-6), 4.80-4.43 (m, 2H, H-3', overlapping with H ₂ O), 4.09-3.88 ( m, 3H, H-1', H-2'), 3.79-3.60 (m, 2H, PCH ₂ ), 1.87 (d, J=1.1Hz, 3H, CH ₃ ); ¹³ C NMR (75MHz, D ₂ O): δ166.7(C-4), 152.0(C-2), 143.5(C-6), 110.2(C-5), 82.0(d, ¹ J _{C, F} ＝168.0Hz, C-3' ),77.5(dd, ² J _C,F ＝18.2Hz, ³ J _C,P ＝11.5Hz,C-2'),66.4(d, ¹ J _C,P ＝156.3Hz,CH ₂ P),47.6( d, ³ J _C,F =7.6Hz, C-1'), 11.0 (CH ₃ ); ³¹ P NMR (121MHz, D ₂ O): δ14.7; HRMS for C ₉ H ₁₄ FN ₂ O ₆ P[ MH] ^- Calculated: 295.0501, Found: 295.0498.

Spectral data were in accordance with literature data (Pomeisl, K.; Pohl, R.; Holy, A.; Votruba, I. Collect. Czech. Chem. Commun. 2005, 70, 1465-1481).

Example 7: Synthesis of (S)-6-chloro-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}purine (10a)

According to the procedure used for the preparation of 6a, from compound 4a (200 mg, 0.82 mmol), compound 9 (150 mg, 0.98 mmol), _Ph3P (430 mg, 1.64 mmol) and DIAD (0.32 mL, 1.64 mmol) in anhydrous THF ( 6 mL) solution started to give compound 10a (190 mg, 60%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 50:1, v/v; DCM/MeOH, 30:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.75(s,1H,H-2),8.32(s,1H,H-8),4.74-4.40(m,4H,H-3',H-1 '), 4.22-3.94(m, 6H, H-2', 2x CH ₂ CH ₃ , PCH ₂ a), 3.78(dd, J=14.0, 8.5Hz, 1H, PCH ₂ b), 1.34-1.24(m ,6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ152.0(C-2,C-4), 151.1(C-6), 146.5(C-8), 131.4(C -5),81.6(d, ¹ J _C,F ＝174.3Hz,C-3'),78.0(dd, ² J _C,F ＝19.6Hz, ³ J _C,P ＝9.0Hz,C-2') ,64.4(d, ¹ J _C,P ＝167.1Hz,CH ₂ P),62.7,62.5(2×d, ² J _C,P ＝6.7Hz,CH ₂ CH ₃ ),44.2(d, ³ J _{C, F} ＝8.0Hz, C-1'), 16.5, 16.4 (2×d, ³ J _{C, P} ＝3.8Hz, CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ20.3; HRMS for Calcd _{. for C13H19ClFN4O4P} [M+H] ⁺ : 381.0889, found _: 381.0884.

Example 8: Synthesis of (R)-6-chloro-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}purine (10b)

From compound 4b (300 mg, 1.23 mmol), compound 9 (230 mg, 1.50 mmol), Ph ₃ P (640 mg, 2.46 mmol) and DIAD (0.48 mL, 2.46 mmol) in anhydrous THF ( 10 mL) solution started to give compound 10b (300 mg, 65%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 50:1, v/v; DCM/MeOH, 30:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.71(s,1H,H-2),8.26(s,1H,H-8),4.69-4.35(m,4H,H-3',H-1 '), 4.17-3.89(m, 6H, H-2', 2x CH ₂ CH ₃ , PCH ₂ a), 3.73(dd, J=14.0, 8.4Hz, 1H, PCH ₂ b), 1.30-1.19(m ,6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ152.0(C-2,C-4), 151.1(C-6), 146.5(C-8), 131.5(C -5),81.6(d, ¹ J _C,F ＝174.3Hz,C-3'),78.1(dd, ² J _C,F ＝19.6Hz, ³ J _C,P ＝8.9Hz,C-2') ,64.5(d, ¹ J _C,P ＝167.0Hz,CH ₂ P),62.7,62.6(2×d, ² J _C,P ＝6.6Hz,CH ₂ CH ₃ ),44.2(d, ³ J _{C, F} ＝8.2Hz, C-1'), 16.5, 16.4 (2×d, ³ J _{C, P} ＝4.5Hz, CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ20.6; HRMS for Calcd _{. for C13H19ClFN4O4P} [M+H] ⁺ : 381.0889, found _: 381.0883.

Example 9: Synthesis of (S)-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}adenine (11a)

A solution of 10a (150 mg, 0.40 mmol) in 10% ethanolamine (20 mL) was stirred at 50 °C for 24 hours. After removal of all volatiles, the residue was purified by silica gel column chromatography (gradient DCM/MeOH, 20:1, v/v; 15:1, v/v) to give 11a as a colorless oil (110 mg, 80 %). ¹ H NMR (300MHz, CDCl ₃ ): δ8.30(s,1H,H-2),8.00(s,1H,H-8),6.75(s,2H,NH ₂ ),4.71-4.27(m, 4H,H-3',H-1'),4.14-3.90(m,6H,H-2',2xCH ₂ CH ₃ ,PCH ₂ a),3.76(dd,J＝13.9,8.9Hz,1H,PCH ₂ b), 1.30-1.22 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ155.0 (C-6), 151.6 (C-2), 159.9 (C-4 ),142.1(C-8),119.2(C-5),82.0(d, ¹ J _C,F ＝173.8Hz,C-3'),78.5(dd, ² J _C,F ＝19.3Hz, ³ J _C,P ＝10.0Hz,C-2'),64.6(d, ¹ J _C,P ＝167.3Hz,CH ₂ P),62.7,62.6(CH ₂ CH ₃ ),43.6(d, ³ J _C,F =8.3Hz, C-1'), 16.5, 16.4 (CH ₂ CH ₃ ); ³¹ PNMR (121MHz, CDCl ₃ ): δ20.5; HRMS for C ₁₃ H ₂₁ FN ₅ O ₄ P[M+H] ⁺ Calculated: 362.1389, Found: 362.1386.

Example 10: Synthesis of (R)-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}adenine (11b)

Following the procedure for the preparation of 11a, starting from compound 10b (300 mg, 0.80 mmol) in 10% ethanolamine (30 mL), compound 11b (260 mg, 90%) was obtained as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 20:1, v/v; 15:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.35(s,1H,H-2),7.95(s,1H,H-8),5.86(s,2H,NH ₂ ),4.74-4.28(m, 4H,H-3',H-1'),4.18-3.91(m,6H,H-2',2xCH ₂ CH ₃ ,PCH ₂ a),3.78(dd,J＝13.9,8.9Hz,1H,PCH ₂ b), 1.34-1.25 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (150 MHz, CDCl ₃ ): δ155.4 (C-6), 153.1 (C-2), 150.2 (C-4 ),141.6(C-8),119.4(C-5),82.0(d, ¹ J _C,F ＝173.8Hz,C-3'),78.5(dd, ² J _C,F ＝19.4Hz, ³ J _C,P ＝9.4Hz,C-2'),64.6(d, ¹ J _C,P ＝167.3Hz,CH ₂ P),62.5,62.4(d, ² J _C,P ＝6.5Hz,CH ₂ CH ₃ ), 43.6 (d, ³ J _{C, F} = 8.1 Hz, C-1'), 16.4, 16.3 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ20.6; HRMS for C ₁₃ H ₂₁ FN ₅ O ₄ P [M+H] ⁺ Calc.: 362.1389, Found: 362.1390.

Example 11: Synthesis of (S)-9-[3-fluoro-2-(phosphonomethoxy)propyl]adenine (12a)

According to the preparation procedure for 8a, from compound 11a (70 mg, 0.19 mmol), bromotrimethylsilane (0.10 mL, 0.77 mmol) and 2,6-lutidine (0.18 mL, 1.59 mmol) in anhydrous acetonitrile (5 mL), compound 12a (38 mg, 65%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/H ₂ O/Et ₃ N, 6:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ8.23(s,1H,H-2),8.14(s,1H,H-8),4.97-4.27(m,4H,H-3',H- 1'),4.05-3.95(m,1H,H-2'),3.55-3.40(m,2H,PCH ₂ ); ¹³ C NMR(75MHz,D ₂ O):δ154.2(C-6), 150.7(C-2), 148.7(C-4), 143.4(C-8), 117.8(C-5), 81.7(d, ¹ J _{C, F} ＝168.0Hz, C-3'), 77.6(dd , ² J _C,F ＝18.9Hz, ³ J _C,P ＝11.4Hz,C-2'),66.1(d, ¹ J _C,P ＝157.0Hz,CH ₂ P),43.3(d, ³ J _{C , F} = 7.5Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ 12.7; HRMS for C ₉ H ₁₃ FN ₅ O ₄ P [MH] ^- calculated: 304.0616, found: 304.0603.

Spectral data correspond to literature data (Jindrich, J.; Holy, A.; Dvorakova, H. Collect. Czech. Chem. Commun. 1993, 58, 1645-1667).

Example 12: Synthesis of (R)-9-[3-fluoro-2-(phosphonomethoxy)propyl]adenine (12b)

According to the preparation procedure for 8a, from compound 11b (250 mg, 0.67 mmol), bromotrimethylsilane (0.37 mL, 2.77 mmol) and 2,6-lutidine (0.64 mL, 5.54 mmol) in anhydrous acetonitrile (10 mL), compound 12b (148 mg, 70%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/H ₂ O/Et ₃ N, 6:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ8.01(d, J=1.0Hz, 1H, H-2), 7.89(d, J=1.0Hz, 1H, H-8), 4.71-4.18(m ,4H,H-3',H-1'),3.96-3.85(m,1H,H-2'),3.62-3.40(m,2H,PCH ₂ ); ¹³ C NMR(75MHz,D ₂ O) : δ154.6(C-6), 151.6(C-2), 148.2(C-4), 142.6(C-8), 117.3(C-5), 81.7(d, ¹ J _{C, F} ＝168.1Hz ,C-3'),77.3(dd, ² J _C,F ＝18.9Hz, ³ J _C,P ＝11.4Hz,C-2'),66.4(d, ¹ J _C,P ＝155.5Hz,CH ₂ P), 43.0 (d, ³ J _{C, F} = 7.4Hz, C-1'); ³¹ P NMR (121MHz, D ₂ O): δ14.2; HRMS for C ₉ H ₁₃ FN ₅ O ₄ P [MH ] ^- Calculated: 304.0616, Found: 304.0609.

Spectral data correspond to literature data (Jindrich, J.; Holy, A.; Dvorakova, H. Collect. Czech. Chem. Commun. 1993, 58, 1645-1667).

Example 13: Synthesis of (S)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-N ⁴ -isobutyrylcytosine (14a)

According to the procedure used for the preparation of 6a, from compound 4a (200 mg, 0.82 mmol), compound 13 (180 mg, 0.98 mmol), Ph ₃ P (430 mg, 1.63 mmol) and DIAD (0.33 mL, 1.63 mmol) in anhydrous THF ( 6 mL) solution started to give compound 14a (130 mg, 40%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 30:1, v/v; DCM/MeOH, 25:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ9.14(s, 1H, NHCO), 7.71(d, J=7.3Hz, 1H, H-6), 7.41(d, J=7.3Hz, 1H, H- 5),4.82-4.31(m,3H,H-3',H-1'a),4.22-3.95(m,7H,H-1'b,H-2',2x CH ₂ CH ₃ ,PCH ₂ a), 3.70(dd, J=13.6, 8.3Hz, 1H, PCH ₂ b), 2.72-2.63(m, 1H, CH(CH ₃ ) ₂ ), 1.36-1.20(m, 12H, 2x CH ₂ CH ₃ , CH(CH ₃ ) ₂ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ177.4(CONH), 163.0(C-4), 156.1(C-2), 150.4(C-6), 96.3(C -5),82.3(d, ¹ J _C,F ＝173.4Hz,C-3'),78.3(dd, ² J _C,F ＝18.3Hz, ³ J _C,P ＝11.9Hz,C-2') ,64.4(d, ¹ J _C,P ＝166.9Hz,CH ₂ P),62.7,62.5(2×d, ² J _C,P ＝6.6Hz,CH ₂ CH ₃ ),51.0(d, ³ J _{C, F} = 8.7Hz, C-1'), 36.7(CH(CH ₃ ) ₂ ), 19.3, 19.1(CH(CH ₃ ) ₂ ), 16.6, 16.5(CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ 20.7; _{HRMS calcd} for _C16H27FN3O6P [M+H] ⁺ : 408.1694, found _: 408.1690.

Example 14: Synthesis of (R)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-N4-isobutyrylcytosine (14b)

From compound 4a (400 mg, 1.64 mmol), compound 9 (360 mg, 1.96 mmol), Ph ₃ P (860 mg, 3.26 mmol) and DIAD (0.66 mL, 3.26 mmol) in anhydrous THF ( 10 mL) solution started to give compound 14b (260 mg, 40%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 30:1, v/v; DCM/MeOH, 25:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.89(s, 1H, NHCO), 7.71(d, J=7.3Hz, 1H, H-6), 7.40(d, J=7.4Hz, 1H, H- 5),4.82-4.31(m,3H,H-3',H-1'a),4.24-3.95(m,7H,H-1'b,H-2',2x CH ₂ CH ₃ ,PCH ₂ a), 3.70(dd, J=13.4, 8.2Hz, 1H, PCH ₂ b), 2.69-2.60(m, 1H, CH(CH ₃ ) ₂ ), 1.35-1.20(m, 12H, 2x CH ₂ CH ₃ , CH(CH ₃ ) ₂ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ177.2(CONH), 162.9(C-4), 156.1(C-2), 150.4(C-6), 96.3(C -5),82.3(d, ¹ J _C,F ＝173.3Hz,C-3'),78.3(dd, ² J _C,F ＝18.4Hz, ³ J _C,P ＝11.8Hz,C-2') ,64.4(d, ¹ J _C,P ＝166.9Hz,CH ₂ P),62.7,62.5(2×d, ² J _C,P ＝6.6Hz,CH ₂ CH ₃ ),51.0(d, ³ J _{C, F} ＝9.1Hz, C-1'), 36.7(CH(CH ₃ ) ₂ ), 19.3, 19.1(CH(CH ₃ ) ₂ ), 16.6, 16.5(CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ 21.4; _{HRMS calcd} for _C16H27FN3O6P [M+H] ⁺ : _408.1694 , found: 408.1691.

Example 15: Synthesis of (S)-O ² -{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-N ⁴ -isobutyrylcytosine (15a)

According to the procedure used for the preparation of 6a, from compound 4a (200 mg, 0.82 mmol), compound 13 (180 mg, 0.98 mmol), Ph ₃ P (430 mg, 1.63 mmol) and DIAD (0.33 mL, 1.63 mmol) in anhydrous THF ( 6 mL) solution started to give compound 15a (150 mg, 45%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 80:1, v/v; DCM/MeOH, 50:1, v/v). ¹ H NMR (600MHz, CDCl ₃ ): δ8.83(s, 1H, NHCO), 8.38(dd, J=5.6, 0.6Hz, 1H, H-6), 7.84(d, J=5.7Hz, 1H, H-5),4.72-4.50(m,3H,H-3',H-1'a),4.38-4.35(m,1H,H-1'b),4.23-4.15(m,5H,H- 2',2x CH ₂ CH ₃ ),4.08(d,J=8.1Hz,2H,PCH ₂ ),2.68-2.61(m,1H,CH(CH ₃ ) ₂ ),1.36-1.33(m,6H,2x CH ₂ CH ₃ ), 1.26-1.25(m, 6H, CH(CH ₃ ) ₂ ); ¹³ C NMR (150MHz, CDCl ₃ ): δ176.8(CONH), 164.1(C-2), 160.6(C- 6),159.5(C-4),104.4(C-5),82.9(d, ¹ J _C,F ＝172.0Hz,C-3'),78.1(dd, ² J _C,F ＝19.1Hz, ³ J _C,P ＝8.9Hz,C-2'),65.0(d, ³ J _C,F ＝8.1Hz,C-1'),64.9(d, ¹ J _C,P ＝195Hz,CH ₂ P), 62.8, 62.6(2×d, ² J _{C, P} ＝6.5Hz, CH ₂ CH ₃ ), 36.6(CH(CH ₃ ) ₂ ), 19.2, 19.1(CH(CH ₃ ) ₂ ), 16.5, 16.4(CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ 20.7; HRMS calcd for C ₁₆ H ₂₇ FN ₃ O ₆ P[M+H] ⁺ : 408.1694, found: 408.1699.

Example 16: Synthesis of (R)-O ² -{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-N ⁴ -isobutyrylcytosine (15b)

From compound 4b (300 mg, 1.64 mmol), compound 13 (360 mg, 1.96 mmol), Ph ₃ P (860 mg, 3.26 mmol) and DIAD (0.66 mL, 3.26 mmol) in anhydrous THF ( 10 mL) solution started to give compound 15b (400 mg, 45%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 80:1, v/v; DCM/MeOH, 50:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.94(s, 1H, NHCO), 8.38(d, J=5.6Hz, 1H, H-6), 7.84(d, J=5.6Hz, 1H, H- 5),4.77-4.48(m,3H,H-3',H-1'a),4.39-4.33(m,1H,H-1'b),4.25-4.07(m,7H,H-2' _{13 _ _ _ _ _ _ _ _} ^_ C NMR (75MHz, CDCl ₃ ): δ176.9(CONH), 164.1(C-2), 160.5(C-6), 159.5(C-4), 104.4(C-5), 82.8(d, ¹ J _C,F ＝172.3Hz,C-3'),78.1(dd, ² J _C,F ＝18.8Hz, ³ J _C,P ＝9.1Hz,C-2'),64.9(d, ³ J _C,F ＝8.2Hz, C-1'), 64.8(d, ¹ J _{C, P} ＝165Hz, CH ₂ P), 62.8, 62.5(d, ² J _{C, P} ＝6.6Hz, CH ₂ CH ₃ ), 36.4( CH(CH ₃ ) ₂ ), 19.2, 19.1 (CH(CH ₃ ) ₂ ), 16.5, 16.4 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ20.9; HRMS for C ₁₆ H ₂₇ FN ₃ O ₆ P [M+H] ⁺ calcd: 408.1694, found: 408.1693.

Example 17: Synthesis of (S)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}cytosine (16a)

A solution of 14a (120 mg, 0.31 mmol) in 30% methanolic ammonia (20 mL) was stirred at 45 °C for 15 h. After removal of all volatiles, the residue was purified by silica gel column chromatography (gradient DCM/MeOH, 10:1, v/v; DCM/MeOH, 8:1, v/v) to afford 16a as a colorless foam ( 90mg, 90%). ¹ H NMR (300MHz, CDCl ₃ ): δ7.40(d, J=7.2Hz, 1H, H-6), 5.92(d, J=7.2Hz, 1H, H-5), 4.77-4.35(m, 2H, H-3'), 4.18-3.95 (m, 7H, H-1', H-2', 2x CH ₂ CH ₃ ), 3.83 (dd, J=13.8, 9.0Hz, 1H, PCH ₂ a) , 3.70 (dd, J=13.4, 7.2Hz, 1H, PCH ₂ b), 1.36-1.30 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ165.8 (C- 4), 156.3(C-2), 147.1(C-6), 94.7(C-5), 82.6(d, ¹ J _{C, F} ＝172.9Hz, C-3'), 78.7(dd, ² J _{C ,F} ＝18.4Hz, ³ J _C,P ＝10.8Hz,C-2'),64.6(d, ¹ J _C,P ＝167.6Hz,CH ₂ P),62.8,62.6(2×d, ² J _{C , P} ＝6.6Hz, CH ₂ CH ₃ ), 50.1 (d, ³ J _{C, F} ＝8.7Hz, C-1'), 16.6, 16.5 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ) : δ 20.4; HRMS calcd for _C12H21FN3O5P [MH ^]+ _{: 338.1275} , found _: 338.1280.

Example 18: Synthesis of (R)-1-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}cytosine (16b)

Following the procedure for the preparation of 16a, starting from compound 14b (200 mg, 0.49 mmol) in 30% methanolic ammonia (20 mL), compound 16b (140 mg, 82%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 10:1, v/v; DCM/MeOH, 8:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ7.35 (d, J=7.2Hz, 1H, H-6), 5.81 (m, d, J=7.2Hz, 1H, H-5), 4.76-4.34( m,2H,H-3'),4.18-3.93(m,7H,H-1',H-2',2x CH ₂ CH ₃ ),3.87-3.66(m,2H,PCH ₂ ),1.36-1.30 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ166.5(C-4), 156.8(C-2), 146.8(C-6), 94.5(C-5 ),82.7(d, ¹ J _C,F ＝172.9Hz,C-3'),78.8(dd, ² J _C,F ＝18.6Hz, ³ J _C,P ＝10.6Hz,C-2'),64.7 (d, ¹ J _C,P ＝167.1Hz, CH ₂ P),62.7,62.6(2×d, ² J _C,P ＝6.4Hz,CH ₂ CH ₃ ),50.1(d, ³ J _C,F ＝ 8.4Hz, C-1'), 16.6, 16.5 (CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ20.9; HRMS for C ₁₂ H ₂₁ FN ₃ O ₅ P[M+H] ⁺ Calculated: 338.1275, Found: 338.1278.

Example 19: Synthesis of (S)-1-[3-fluoro-2-(phosphonomethoxy)propyl]cytosine (17a)

According to the preparation procedure for 8a, from compound 16a (100 mg, 0.30 mmol), bromotrimethylsilane (0.16 mL, 1.19 mmol) and 2,6-lutidine (0.27 mL, 2.37 mmol) in anhydrous acetonitrile (5 mL), compound 17a (58 mg, 70%) was obtained as a white foam. By silica gel column chromatography (gradient: acetone/H ₂ O/Et ₃ N, 6:1:1, v/v/v; acetone/H ₂ O/Et ₃ N, 5:1:1, v/v/v ) to purify the crude residue. ¹ H NMR (600MHz, D ₂ O): δ7.75-7.74 (m, 1H, H-6), 6.07-6.06 (m, 1H, H-5), 4.80-4.48 (m, 1H, H-3 ', overlapping with _H2O ), 4.14 (dd, J=14.1, 3.4Hz, 1H, H-1'a), 3.98-3.88 (m, 2H, H-2', H-1'b), 3.77 (dd, J=13.1, 9.1Hz, 1H, PCH ₂ a), 3.59 (dd, J=13.1, 9.6Hz, 1H, PCH ₂ b); ¹³ C NMR (75MHz, D ₂ O): δ162.4( C-4), 153.0(C-2), 149.0(C-6), 94.5(C-5), 82.0(d, ¹ J _{C, F} ＝167.9Hz, C-3'), 77.4(dd, ² J _C,F ＝18.4Hz, ³ J _C,P ＝11.5Hz,C-2'),66.1(d, ¹ J _C,P ＝157.2Hz,CH ₂ P),49.1(d, ³ J _C,F = 7.9 Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ 14.9; HRMS for C ₈ H ₁₃ FN ₃ O ₅ P [MH] ^- calcd: 280.0504, found: 280.0501.

Spectral data were in accordance with literature data (Yu, K.L.; Bronson, J.J.; Yang, H.; Patick, A.; Alam, M.; Brankovan, V.; Datema, R.; Hitchcock, M.J.M.; Martin, J.C.J. Med. Chem. 1993, 36, 2726-2738).

Example 20: Synthesis of (R)-1-[3-fluoro-2-(phosphonomethoxy)propyl]cytosine (17b)

According to the preparation procedure for 8a, from compound 16b (140 mg, 0.42 mmol), bromotrimethylsilane (0.22 mL, 1.66 mmol) and 2,6-lutidine (0.38 mL, 3.32 mmol) in anhydrous acetonitrile (5 mL), compound 17b (82 mg, 70%) was obtained as a white foam. By silica gel column chromatography (gradient: acetone/H ₂ O/Et ₃ N, 6:1:1, v/v/v; acetone/H ₂ O/Et ₃ N, 5:1:1, v/v/v ) to purify the crude residue. ¹ H NMR (300MHz, D ₂ O): δ7.72(d, J=7.6Hz, 1H, H-6), 6.05(d, J=7.5Hz, 1H, H-5), 4.82-4.45(m , 1H, H-3', overlapping with H ₂ O), 4.18-4.12 (m, 1H, H-1'a), 4.02-3.75 (m, 3H, H-2', H-1'b, PCH ₂ a), 3.64-3.57 (m, 1H, PCH ₂ b); ¹³ C NMR (75MHz, D ₂ O): δ163.9 (C-4), 155.0 (C-2), 148.4 (C-6) ,94.7(C-5),82.1(d, ¹ J _C,F ＝167.7Hz,C-3'),77.6(dd, ² J _C,F ＝18.3Hz, ³ J _C,P ＝11.6Hz,C -2'), 66.2(d, ¹ J _{C, P} ＝157.1Hz, CH ₂ P), 49.2(d, ³ J _{C, F} ＝7.9Hz, C-1'); ³¹ P NMR (121MHz, D ₂ O): δ 14.9; HRMS for C ₈ H ₁₃ FN ₃ O ₅ P [MH] ^- calcd: 280.0504, found: 280.0507.

Spectral data were in accordance with literature data (Yu, K.L.; Bronson, J.J.; Yang, H.; Patick, A.; Alam, M.; Brankovan, V.; Datema, R.; Hitchcock, M.J.M.; Martin, J.C.J. Med. Chem. 1993, 36, 2726-2738).

Example 21: Synthesis of (S)-O ² -{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}cytosine (18a)

Following the procedure for the preparation of 16a, starting from compound 15a (150 mg, 0.37 mmol) in 30% methanolic ammonia (15 mL), compound 18a (100 mg, 82%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 25:1, v/v; DCM/MeOH, 20:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ7.92(dd, J=5.7Hz, 1H, H-6), 6.11(d, J=5.7Hz, 1H, H-5), 5.71(s, 2H, NH ₂ ),4.71-4.60(m,1H,H-3'a),4.56-4.44(m,1H,H-3'b),4.41-4.31(m,2H,H-1'),4.19- 3.96(m,7H,2x CH ₂ CH3,H-2',PCH ₂ ), 1.32-1.27(m,6H,2x CH ₂ CH ₃ ); ¹³ C NMR(75MHz,CDCl ₃ ): δ165.3(C -4),164.7(C-2),157.1(C-6),100.1(C-5),83.0(d, ¹ J _C,F ＝172.2Hz,C-3'),78.8(dd, ² J _C,F ＝19.0Hz, ³ J _C,P ＝11.3Hz,C-2'),64.8(d, ¹ J _C,P ＝165.0Hz,CH ₂ P),64.6(d, ³ J _C,F ＝ 8.3Hz, C-1'), 62.9, 62.7 (2×d, ² J _{C, P} = 6.4Hz, CH ₂ CH ₃ ), 16.5, 16.4 (CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ 20.5; HRMS calcd for C ₁₂ H ₂₁ FN ₃ O ₅ P [M+H] ⁺ : 338.1276, found: 338.1292.

Example 22: Synthesis of (R)-O ² -{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}cytosine (18b)

Following the procedure for the preparation of 16a, starting from compound 15b (250 mg, 0.60 mmol) in 30% methanolic ammonia (20 mL), compound 18b (190 mg, 90%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 25:1, v/v; DCM/MeOH, 20:1, v/v). ¹ H NMR (500MHz, CDCl ₃ ): δ7.92(dd, J=5.7Hz, 1H, H-6), 6.11(d, J=5.7Hz, 1H, H-5), 5.71(s, 2H, NH ₂ ),4.67-4.48(m,2H,H-3'),4.39-4.32(m,1H,H-1'),4.17-4.11(m,4H,2x CH ₂ CH ₃ ),4.06-3.98 (m, 3H, H-2', PCH ₂ ), 1.31-1.28 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (125MHz, CDCl ₃ ): δ165.3(C-4), 164.7( C-2),157.0(C-6),100.1(C-5),83.0(d, ¹ J _C,F ＝172.2Hz,C-3'),78.8(dd, ² J _C,F ＝18.9Hz , ³ J _C,P ＝11.3Hz,C-2'),64.8(d, ¹ J _C,P ＝162.5Hz,CH ₂ P),64.6(d, ³ J _C,F ＝8.5Hz,C-1 '), 62.9, 62.7 (2×d, ² J _{C, P} = 6.6Hz, CH ₂ CH ₃ ), 16.5, 16.4 (CH ₂ CH ₃ ); ³¹ P NMR (202MHz, CDCl ₃ ): δ20.5; HRMS calcd _{for C12H21FN3O5P} [M+H] ⁺ : 338.1276, _{found :} 338.1271.

Example 23: Synthesis of (S)-O ² -[3-fluoro-2-(phosphonomethoxy)propyl]cytosine (19a)

According to the preparation procedure for 8a, from compound 18a (100 mg, 0.30 mmol), bromotrimethylsilane (0.16 mL, 1.20 mmol) and 2,6-lutidine (0.27 mL, 2.37 mmol) in anhydrous acetonitrile (5 mL), compound 19a (82 mg, 70%) was obtained as a white foam. By silica gel column chromatography (gradient: acetone/H ₂ O/Et ₃ N, 5:1:1, v/v/v; acetone/H ₂ O/Et ₃ N, 4:1:1, v/v/v ) to purify the crude residue. ¹ H NMR (300MHz, D ₂ O): δ7.75(d, J=6.0Hz, 1H, H-6), 6.16(d, J=6.0Hz, 1H, H-5), 4.75-4.46(m ,2H,H-3'),4.27(d,J=5.0Hz,2H,H-1'),3.98-3.87(m,1H,H-2'),3.53(d,J=9.1Hz,2H , PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ165.3(C-4), 163.7(C-2), 155.6(C-6), 100.2(C-5), 82.3(d, ¹ J _C,F ＝165.9Hz,C-3'),78.9(dd, ² J _C,F ＝18.6Hz, ³ J _C,P ＝10.9Hz,C-2'),67.8(d, ¹ J _{C , P} = 149.9Hz, CH ₂ P), 64.2 (d, ³ J _{C, F} = 7.6Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ12.7; HRMS for C ₈ H ₁₃ FN ₃ O ₅ P [MH] ^- Calculated: 280.0504, Found: 280.0505.

Example 24: Synthesis of (R)-O ² -[3-fluoro-2-(phosphonomethoxy)propyl]cytosine (19b)

According to the preparation procedure for 8a, from compound 18b (200 mg, 0.60 mmol), bromotrimethylsilane (0.32 mL, 2.20 mmol) and 2,6-lutidine (0.54 mL, 4.80 mmol) in anhydrous acetonitrile (10 mL), compound 19b (160 mg, 70%) was obtained as a white foam. By silica gel column chromatography (gradient: acetone/H ₂ O/Et ₃ N, 5:1:1, v/v/v; acetone/H ₂ O/Et ₃ N, 4:1:1, v/v/v ) to purify the crude residue. ¹ H NMR (300MHz, D ₂ O): δ7.74 (d, J=6.1Hz, 1H, H-6), 6.15 (dd, J=6.0, 1.0Hz, 1H, H-5), 4.75-4.46 (m,2H,H-3'),4.33-4.23(m,2H,H-1'),4.03-3.91(m,1H,H-2'),3.65(d,J＝9.2Hz,2H, PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ165.2(C-4), 163.4(C-2), 155.1(C-6), 100.2(C-5), 82.3(d, ¹ J _C,F ＝166.5Hz,C-3'),77.2(dd, ² J _C,F ＝18.6Hz, ³ J _C,P ＝10.9Hz,C-2'),66.7(d, ¹ J _{C, P} = 154.2Hz, CH ₂ P), 64.3 (d, ³ J _{C, F} = 7.7Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ14.2; HRMS for C ₈ H _{13 FN3O5P} [MH] ^- Calculated: 280.0504, Found: _280.0513 .

Example 25: Synthesis of (S)-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-O ⁶ -benzylguanine (21a)

From compound 4a (300 mg, 1.23 mmol), compound 20 (360 mg, 1.47 mmol), Ph ₃ P (650 mg, 2.46 mmol) and DIAD (0.48 mL, 2.46 mmol) in anhydrous THF ( 8 mL) solution started to give compound 21a (290 mg, 50%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 40:1, v/v; DCM/MeOH, 30:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ7.70(s,1H,H-8),7.51-7.29(m,5H,ArH),5.56(s,2H,CH ₂ -Ar),5.01(s, 2H,NH ₂ ),4.69-4.28(m,3H,H-3',H-1'a),4.20-4.01(m,6H,H-1'b,H-2',2x CH ₂ CH ₃ ), 3.95-3.77 (m, 2H, PCH ₂ ), 1.34-1.23 (m, 6H, 2xCH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ161.1 (C-6), 159.4 (C -2), 154.2(C-4), 140.3(C-8), 136.5(Ar-C), 128.4(Ar-C), 128.3(Ar-C), 128.0(Ar-C), 115.4(C- 5),82.1(d, ¹ J _C,F ＝173.5Hz,C-3'),78.6(dd, ² J _C,F ＝19.3Hz, ³ J _C,P ＝10.3Hz,C-2'), 68.1 (CH ₂ -Ar), 64.6 (d, ¹ J _{C, P} ＝166.9Hz, CH ₂ P), 62.7, 62.6 (2×d, ² J _{C, P} ＝7.0Hz, CH ₂ CH ₃ ), 44.3 (d, ³ J _{C, F} = 7.9Hz, C-1'), 16.5, 16.4 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ19.9; HRMS for C ₂₀ H ₂₇ FN ₅ O ₅ P[M+H] ⁺ calcd: 468.1806, found: 468.1801.

Example 26: Synthesis of (R)-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}-O ⁶ -benzylguanine (21b)

According to the procedure used for the preparation of 6a, from compound 4b (300 mg, 1.23 mmol), compound 20 (360 mg, 1.47 mmol), _Ph3P (650 mg, 2.46 mmol) and DIAD (0.48 mL, 2.46 mmol) in anhydrous THF ( 8 mL) solution started to give compound 21b (250 mg, 44%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 40:1, v/v; DCM/MeOH, 30:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ7.70(s,1H,H-8),7.52-7.28(m,5H,ArH),5.57(s,2H,CH ₂ -Ar),4.94(s, 2H,NH ₂ ),4.64-4.28(m,3H,H-3',H-1'a),4.21-4.00(m,6H,H-1'b,H-2',2x CH ₂ CH ₃ ), 3.95-3.77 (m, 2H, PCH ₂ ), 1.34-1.24 (m, 6H, 2xCH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ161.2 (C-6), 159.4 (C -2), 154.3(C-4), 140.4(C-8), 136.5(Ar-C), 128.4(d, J＝8.2Hz, Ar-C), 128.1(Ar-C), 115.4(C- 5),82.2(d, ¹ J _C,F ＝173.5Hz,C-3'),78.6(dd, ² J _C,F ＝19.3Hz, ³ J _C,P ＝10.1Hz,C-2'), 68.2 (CH ₂ -Ar), 64.7 (d, ¹ J _{C, P} ＝167.0Hz, CH ₂ P), 62.7, 62.6 (2×d, ² J _{C, P} ＝7.0Hz, CH ₂ CH ₃ ), 44.3 (d, ³ J _{C, F} = 8.1Hz, C-1'), 16.5, 16.4 (2×d, ³ J _{C, P} = 2.9Hz, CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ) : δ 20.5; HRMS calcd for _C20H27FN5O5P [M+H] ⁺ : _468.1806 , found _{: 468.1811} .

Example 27: Synthesis of (S)-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}guanine (22a)

Compound 21a (300 mg, 0.64 mmol) and Pd/C on charcoal (10% w/w, 150 mg) were suspended in EtOAc (20 mL), and the solution was purged first with nitrogen and then hydrogen and allowed to Stir down. After 10 hours, the mixture was filtered through a pad of celite, and the filtrate was evaporated under reduced pressure to give the crude product. The residue was purified by silica gel column chromatography (gradient DCM/MeOH, 10:1, v/v; 7:1, v/v) to afford 22a (170 mg, 70%) as a colorless foam. ¹ H NMR (300MHz, MeOD): δ7.74(s,1H,H-8),4.77-4.37(m,2H,H-3'),4.33-3.85(m,9H,H-1',H -2', 2x CH ₂ CH ₃ , PCH ₂ ), 1.31-1.23 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, MeOD): δ159.5(C-6), 155.3(C -2),153.4(C-4),140.4(C-8),117.3(C-5),83.2(d, ¹ J _C,F ＝171.7Hz,C-3'),79.9(dd, ² J _C,F ＝19.1Hz, ³ J _C,P ＝11.9Hz,C-2'),64.5(d, ¹ J _C,P ＝165.0Hz,CH ₂ P),64.3,64.1(2×d, ² J _{C, P} = 6.6Hz, CH ₂ CH ₃ ), 44.3 (d, ³ J _{C, F} = 8.6 Hz, C-1'), 16.7, 16.6 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, MeOD) : δ 21.1; _HRMS calcd for _C13H21FN5O5P [M+H] ⁺ : 378.1337, _{found :} 378.1329.

Example 28: Synthesis of (R)-9-{3-fluoro-2-[(diethylphosphoryl)methoxy]propyl}guanine (22b)

Following the general procedure used for the preparation of 22a starting from compound 21b (250 mg, 0.54 mmol) and Pd/C on charcoal (10% w/w, 120 mg) in EtOAc (30 mL) afforded compound 23b as a colorless foam (160 mg, 80%). The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 10:1, v/v; 7:1, v/v). ¹ H NMR (300MHz, MeOD): δ7.74(s,1H,H-8),4.76-4.37(m,2H,H-3'),4.33-3.85(m,9H,H-1',H -2', 2x CH ₂ CH ₃ , PCH ₂ ), 1.31-1.23(m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, MeOD): δ159.5(C-6), 155.4(C -2),153.4(C-4),140.4(C-8),117.3(C-5),83.2(d, ¹ J _C,F ＝171.6Hz,C-3'),79.9(dd, ² J _C,F ＝19.0Hz, ³ J _C,P ＝11.9Hz,C-2'),64.5(d, ¹ J _C,P ＝165.0Hz,CH ₂ P),64.3,64.1(2×d, ² J _{C, P} = 6.6Hz, CH ₂ CH ₃ ), 44.3 (d, ³ J _{C, F} = 8.6 Hz, C-1'), 16.7, 16.6 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, MeOD) : δ 21.1; _HRMS calcd for _C13H21FN5O5P [M+H] ⁺ : 378.1337, _{found :} 378.1329.

Example 29: Synthesis of (S)-9-[3-fluoro-2-(phosphonomethoxy)propyl]guanine (23a)

According to the preparation procedure for 8a, from compound 22a (170 mg, 0.45 mmol), bromotrimethylsilane (0.24 mL, 1.80 mmol) and 2,6-lutidine (0.42 mL, 3.60 mmol) in anhydrous acetonitrile (5 mL), compound 23a (87 mg, 60%) was obtained as a white foam. By silica gel column chromatography (gradient: acetone/H ₂ O/Et ₃ N, 5:1:1, v/v/v; acetone/H ₂ O/Et ₃ N, 4:1:1, v/v/v ) to purify the crude residue. ¹ H NMR (300MHz, D ₂ O): δ7.74(s,1H,H-8),4.79-4.59(m,4H,H-3',H-1'),3.97-3.88(m,1H , H-2'), 3.51-3.39 (m, 2H, PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ166.8 (C-6), 160.0 (C-2), 151.2 (C- 4),138.8(C-8),116.7(C-5),81.9(d, ¹ J _C,F ＝167.4Hz,C-3'),77.2(dd, ² J _C,F ＝18.7Hz, ³ J _C,P ＝10.6Hz,C-2'),68.0(d, ¹ J _C,P ＝150.0Hz,CH ₂ P),42.2(d, ³ J _C,F ＝7.1Hz,C-1') ; ³¹ P NMR (121 MHz, D ₂ O): δ 13.6; HRMS for C ₉ H ₁₃ FN ₅ O ₅ P [MH] ^- calcd: 320.0565, found: 320.0565.

Spectral data were in accordance with literature data (Baszczynski, O.; Hockova, D.; Janeba, Z.; Holy, A.; Jansa, P.; Dracinsky, M.; Keough, D.T.; Guddat, L.W. Eur. J. Med. Chem .2013, 67, 81-89).

Example 30: Synthesis of (R)-9-[3-fluoro-2-(phosphonomethoxy)propyl]guanine (23b)

According to the preparation procedure for 8a, from compound 22b (160 mg, 0.42 mmol), bromotrimethylsilane (0.22 mL, 1.70 mmol) and 2,6-lutidine (0.39 mL, 3.40 mmol) in anhydrous acetonitrile (5 mL), compound 23b (87 mg, 60%) was obtained as a white foam. By silica gel column chromatography (gradient: acetone/H ₂ O/Et ₃ N, 5:1:1, v/v/v; acetone/H ₂ O/Et ₃ N, 4:1:1, v/v/v ) to purify the crude residue. ¹ H NMR (300MHz, D ₂ O): δ7.76(s, 1H, H-8), 4.70-4.29(m, 2H, H-3'), 4.25-4.09(m, 2H, H-1'),4.02-3.88(m,1H,H-2'),3.65-3.47(m,2H,PCH ₂ ); ¹³ CNMR(75MHz,D ₂ O): δ158.4(C-6),153.3(C -2),151.2(C-4),140.3(C-8),115.2(C-5),81.9(d, ¹ J _C,F ＝167.9Hz,C-3'),77.5(dd, ² J _C,F ＝18.7Hz, ³ J _C,P ＝11.3Hz,C-2'),66.4(d, ¹ J _C,P ＝156.0Hz,CH ₂ P),42.7(d, ¹ J _C,F ＝ 7.6 Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ 14.5; HRMS for C ₉ H ₁₃ FN ₅ O ₅ P [MH] ^- calcd: 320.0565, found: 320.0571.

Spectral data were in accordance with literature data (Baszczynski, O.; Hockova, D.; Janeba, Z.; Holy, A.; Jansa, P.; Dracinsky, M.; Keough, D.T.; Guddat, L.W. Eur. J. Med. Chem .2013, 67, 81-89).

Examples 31-40: Synthesis of aryloxyaminophosphonate prodrugs of the free phosphates 8a-b, 12a-b, 17a-b, 19a-b and 23a-b.

General procedure

The relevant phosphonic acid (1 equiv.) was mixed with a solution of L-aspartate HCl salt (1.7 equiv.) and phenol (4.4 equiv.) in dry pyridine. Then, Et ₃ N (10 equiv) was added, and the mixture was stirred at 60° C. under nitrogen atmosphere for 15-20 minutes. 2,2'-Dithiobipyridine (7 equiv) was mixed with _PPh (7 equiv) in anhydrous pyridine in a separate flask, and the resulting mixture was stirred for 10-15 min to give a clear pale yellow solution. Then, this solution was added to the above solution, and the combined mixture was stirred at 60° C. for 12 hours. Then, the mixture was concentrated under reduced pressure to give a residue, which was redissolved in EtOAc. The solution was washed with saturated aqueous NaHCO ₃ and brine, the organic layer was separated, dried over Na ₂ SO ₄ , filtered, and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography to afford the desired aminophosphonate.

The following compounds were prepared according to this procedure:

Example 31: (S)-1-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}thymine (24a)

According to the general procedure, from compound 8a (50 mg, 0.17 mmol), aspartate HCl salt (90 mg, 0.29 mmol), PhOH (70 mg, 0.75 mmol), Et ₃ N (0.24 mL, 1.7 mmol), 2,2 Starting with anhydrous pyridine (5 mL) of '-dithiobipyridine (260 mg, 1.20 mmol) and _PPh3 (310 mg, 1.20 mmol) afforded compound 24a (45 mg, 45%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 60:1, v/v; 50:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ9.35(s,1H,NHCO),7.36-7.13(m,6H,H-6,ArH),4.72-3.65(m,13H,H-3', H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.77-2.49(m,2H,H-β-Asp),1.74( d,J=1.2Hz,3H,CH ₃ -5), 1.71(d,J=1.2Hz,3H,CH ₃ -5),1.60-1.50(m,4H,2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ), 1.35-1.26 (m, 8H, 2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ), 0.91-0.85 (m, 6H, 2x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.9(d, ³ J _{C, P} ＝4.7Hz, CO-α), 172.6(d, ³ J _{C, P} ＝4.6Hz, CO-α), 171.5(CO- β), 165.3(C-4), 152.3, 152.2(C-2), 151.3(Ar-C), 143.0(C-6), 130.7(Ar-C), 125.9, 125.8(Ar-C), 121.9 (d, ³ J _C,P ＝4.3Hz,Ar-C),121.7(d, ³ J _C,P ＝4.5Hz,Ar-C),110.4,110.3(C-5),83.5(d, ¹ J _C,F ＝172.5Hz,C-3'),83.2(d, ¹ J _C,F ＝165.0Hz,C-3'),79.9,79.8,79.7,79.6,79.5,79.4,79.2(C-2' ), 66.9(d, ¹ J _{C, P} ＝157.5Hz, CH ₂ P), 66.5, 66.4, 65.8, 65.7 (OCH ₂ (CH ₂ ) ₃ CH ₃ ), 51.5, 51.4 (C-1'), 49.0 ,48.8(C-α-Asp),39.8(d, ³ J _C,P ＝4.0Hz,C-β-Asp),39.6(d, ³ J _C,P ＝4.1Hz,C-β-Asp), 29.0, 28.9, 28.7, 28.6 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 (O(CH ₂ ) ₄ CH ₃ ), 12.3 ( _CH3-5 ); ³¹ P NMR (121 MHz, CD ₃ CN): δ 22.3, 21.3; HRMS calcd for C ₂₉ H ₄₃ FN ₃ O ₉ P[M+Na] ⁺ : 650.2613, found: 650.2629.

Example 32: (R)-1-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}thymine (24b)

According to the general procedure, from compound 8b (80 mg, 0.27 mmol), aspartate HCl salt (142 mg, 0.46 mmol), PhOH (112 mg, 1.20 mmol), Et ₃ N (0.38 mL, 2.70 mmol), 2,2 Starting with anhydrous pyridine (5 mL) of '-dithiobipyridine (420 mg, 1.90 mmol) and _PPh3 (500 mg, 1.90 mmol) afforded compound 24b (80 mg, 50%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 60:1, v/v; 50:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ9.59(s,1H,NHCO),7.39-7.13(m,6H,H-6,ArH),4.77-3.71(m,13H,H-3', H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.82-2.53(m,2H,H-β-Asp),1.79( s,3H,CH ₃ -5),1.73(s,3H,CH ₃ -5),1.64-1.55(m,4H,2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ),1.41-1.28(m, 8H, 2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ), 0.97-0.88 (m, 6H, 2x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172. 8(d, ³ J _{C, P} ＝5.0Hz, CO-α), 172.6 (d, ³ J _{C, P} ＝4.5Hz, CO-α), 171.6, 171.5 (CO-β), 165.4 (C-4 ), 152.3(C-2), 151.4, 151.3(Ar-C), 143.1, 143.0(C-6), 130.7, 130.6(Ar-C), 125.8(Ar-C), 121.8(d, ³ J _{C ,P} ＝4.0Hz,Ar-C),121.7(d, ³ J _C,P ＝4.4Hz,Ar-C),110.4,110.3(C-5),83.4(d,J＝172.5Hz,C-3 '),82.2(d, ¹ J _C,F ＝165.0Hz,C-3'),79.8,79.6,79.5,79.4,79.2(C-2'),66.9(d, ¹ J _C,P ＝157.5Hz , CH ₂ P), 66.5, 66.4, 65.7 (OCH ₂ (CH ₂ ) ₃ CH ₃ ), 51.5 (C-1'), 49.0 (d, ² J _{C, P} = 8.3 Hz, C-α-Asp) ,48.8(d, ² J _C,P ＝8.0Hz,C-α-Asp),39.7(d, ³ J _C,P ＝4.0Hz,C-β-Asp),39.6(d, ³ J _C,P =4.6Hz, C-β-Asp), 29.0, 28.9, 28.7, 28.6 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 ( O(CH ₂ ) ₄ CH ₃ ),1 2.3 (CH ₃ -5); ³¹ P NMR (121 MHz, CD ₃ CN): δ 22.2, 21.5; HRMS for C ₂₉ H ₄₃ FN ₃ O ₉ P [MH] - calcd: 626.2648, found: 626.2648.

Example 33: (S)-9-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}adenine (25a)

According to the general procedure, from compound 12a (30 mg, 0.10 mmol), aspartate HCl salt (52 mg, 0.17 mmol), PhOH (40 mg, 0.43 mmol), Et ₃ N (0.14 mL, 1.00 mmol), 2,2 Starting with anhydrous pyridine (3 mL) of '-dithiobipyridine (150 mg, 0.69 mmol) and _PPh3 (180 mg, 0.69 mmol) afforded compound 25a (26 mg, 40%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 25:1, v/v; 20:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ8.25(s,1H,H-2),8.22(s,1H,H-2),7.99(s,1H,H-8),7.97(s, 1H,H-8),7.37-7.05(m,6H,ArH),6.02(s,2H,NH ₂ ),4.75-3.83(m,13H,H-3',H-2',H-1' ,2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.79-2.53(m,2H,H-β-Asp),1.61-1.53(m,4H,2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ),1.36-1.28(m,8H,2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ),0.93-0.87(m,6H,O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.9(d, ³ J _{C, P} ＝4.4Hz, CO-α), 172.6(d, ³ J _{C, P} ＝4.7Hz, CO-α ), 171.5, 171.4 (CO-β), 156.9 (C-6), 153.8, 153.7 (C-2), 151.4, 151.2, 151.1 (Ar-C, C-4), 142.9, 142.8 (C-8) ,130.6(Ar-C),125.8,125.7(Ar-C),121.9(d, ³ J _C,P ＝4.4Hz,Ar-C),121.7(d, ³ J _C,P ＝4.4Hz,Ar- C),120.1,120.0(C-5),83.3(d, ¹ J _C,F ＝165.0Hz,C-3'),83.1(d, ¹ J _C,F ＝172.5Hz,C-3'), 79.9,79.8,79.7,79.5,79.4,79.3(C-2'),67.0(d, ¹ J _C,P ＝157.5Hz,CH ₂ P),66.7(d, ¹ J _C,P ＝157.5Hz,CH ₂ P),66.5,66.4,65.8,65.7(OCH ₂ (CH ₂ ) ₃ CH ₃ ),51.6,51.5(C-1'),44.3(d, ² J _C,P ＝2.4Hz,C-α- Asp), 44.2(d, ² J _{C, P} ＝2.4Hz, C-α-Asp), 39.8(d, ³ J _{C, P} ＝3.9Hz, C-β-Asp), 39.6(d, ³ J _{C , P} = 4.2Hz, C-β-Asp), 29.0, 28.9, 28.7, 28 .6(OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9(O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3(O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121MHz, CD ₃ CN): δ 22.2, 21.2; HRMS calcd for C ₂₉ H ₄₂ FN ₆ O ₇ P [M+H] ⁺ : 637.2909, found: 637.2913.

Example 34: (R)-9-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}adenine (25b)

According to the general procedure, from compound 12b (80 mg, 0.26 mmol), aspartate HCl salt (140 mg, 0.45 mmol), PhOH (110 mg, 1.15 mmol), Et ₃ N (0.36 mL, 2.60 mmol), 2,2 Starting with anhydrous pyridine (5 mL) of '-dithiobipyridine (400 mg, 1.83 mmol) and _PPh3 (480 mg, 1.83 mmol), afforded compound 25b (110 mg, 55%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 25:1, v/v; 20:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ8.26(s, 1H, H-2), 8.05(s, 1H, H-8), 8.03(s, 1H, H-8), 7.35-7.01( m,5H,ArH),6.02(s,2H,NH ₂ ),4.87-3.90(m,13H,H-3',H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.82-2.56(m,2H,H-β-Asp),1.57-1.48(m,4H,OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ),1.32 -1.24(m, 8H, 2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ), 0.90-0.81(m, 6H, 2x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.8(d, ³ J _{C, P} ＝5.0Hz, CO-α), 172.7(d, ³ J _{C, P} ＝4.4Hz, CO-α), 171.5, 171.4 (CO-β), 157.0(C-6),153.8(C-2),151.3,151.2,151.1,151.0(Ar-C,C-4),142.8(C-8),130.6,130.5(Ar-C),125.7(Ar -C), 121.7(d, ³ J _{C, P} ＝4.6Hz, Ar-C), 119.9(C-5), 83.3(d, ¹ J _{C, F} ＝172.5Hz, C-3'), 83.1( d, ¹ J _C,F ＝172.5Hz,C-3'),79.7,79.6,79.5,79.4,79.3(C-2'),66.8(d, ¹ J _C,P ＝150.0Hz,CH ₂ P) ,66.6(d, ¹ J _C,P ＝157.5Hz,CH ₂ P),66.4,65.7(OCH ₂ (CH ₂ ) ₃ CH ₃ ),51.5(C-1'),44.2(d, ² J _{C, P} ＝8.2Hz, C-α-Asp), 44.0(d, ² J _{C, P} ＝7.8Hz, C-α-Asp), 39.7(d, ³ J _{C, P} ＝3.9Hz, C-β-Asp ), 39.6(d, ³ J _{C, P} ＝3.8Hz, C-β-Asp), 28.9, 28.8, 28.7, 28.6(OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9(O(CH ₂ ) ₃ CH ₂ CH ₃ ),14.2(O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121 MHz, CD ₃ CN): δ 22.1, 21.5; HRMS for C ₂₉ H ₄₂ FN ₆ O ₇ P [MH] - calcd: 635.2764, found: 635.2775.

Example 35: (S)-1-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}cytosine (26a)

According to the general procedure, from compound 17a (40 mg, 0.14 mmol), aspartate HCl salt (75 mg, 0.24 mmol), PhOH (59 mg, 0.63 mmol), Et ₃ N (0.20 mL, 1.40 mmol), 2,2 Starting with anhydrous pyridine (3 mL) of '-dithiobipyridine (220 mg, 1.00 mmol) and _PPh3 (260 mg, 1.00 mmol) afforded compound 26a (23 mg, 26%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 20:1, v/v; 10:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ7.45-7.16 (m, 6H, ArH, H-6), 5.95 (s, 2H, NH ₂ ), 5.70 (s, 1H, H-5), 5.68 (s,1H,H-5),4.75-3.66(m,13H,H-3',H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α -Asp,NHPO),2.82-2.56(m,2H,H-β-Asp),1.63-1.55(m,4H,2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ),1.35-1.27(m,8H ,2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ),0.94-0.88(m,6H,O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.9( d, ³ J _C,P ＝4.7Hz,CO-α),172.7(d, ³ J _C,P ＝4.5Hz,CO-α),171.5(CO-β),167.5(C-4),157.5, 157.4(C-2), 151.5, 151.4, 151.3, 151.2(Ar-C), 148.2(C-6), 130.7, 130.6(Ar-C), 125.8, 125.7(Ar-C), 122.0(d, ³ J _C,P ＝4.4Hz,Ar-C),121.8(d, ³ J _C,P ＝4.4Hz,Ar-C),94.2,94.1(C-5),83.8(d, ¹ J _C,F ＝ 172.5Hz,C-3'),83.4(d, ¹ J _C,F ＝165.0Hz,C-3'),80.0,79.8,79.7,79.6,79.5,79.4,79.3(C-2'),66.9( d, J＝150.0Hz, CH ₂ P), 66.8 (d, ¹ J _{C, P} ＝150.0 Hz, CH ₂ P), 66.5, 66.4, 65.8, 65.7 (OCH ₂ (CH ₂ ) ₃ CH ₃ ), 51.6 ,51.5(C-1'),50.6,50.5,50.4(C-α-Asp),39.8(d, ³ J _C,P ＝4.0Hz,C-β-Asp),39.5(d, ³ J _{C, P} = 4.2 Hz, C-β-Asp), 29.0, 28.9, 28.8, 28.7 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 (O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121 MHz, CD ₃ CN): δ 22.4, 21.4; HRMS calcd for C ₂₈ H ₄₂ FN ₄ O ₈ P [M+H] ⁺ : 613.2797, found: 613.2802.

Example 36: (R)-1-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}cytosine (26b)

According to the general procedure, from compound 17b (40 mg, 0.14 mmol), aspartate HCl salt (75 mg, 0.24 mmol), PhOH (59 mg, 0.63 mmol), Et ₃ N (0.20 mL, 1.40 mmol), 2,2 Starting with anhydrous pyridine (3 mL) of '-dithiobipyridine (220 mg, 1.00 mmol) and _PPh3 (260 mg, 1.00 mmol) afforded compound 26b (20 mg, 20%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 20:1, v/v; 10:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ7.45-7.13 (m, 6H, ArH, H-6), 5.74-5.69 (m, 1H, H-5), 4.78-3.70 (m, 13H, H -3',H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.82-2.56(m,2H,H-β-Asp ),1.64-1.52(m,4H,2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ),1.40-1.24(m,8H,2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ),0.93- 0.87(m, 6H, 2x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.8(d, ³ J _{C, P} = 5.1Hz, CO-α), 172.7( d, ³ J _C,P ＝4.4Hz,CO-α),171.6,171.5(CO-β),167.5(C-4),157.5,157.4(C-2),151.5,151.3,151.2(Ar-C ), 148.2, 148.1(C-6), 130.6(Ar-C), 125.8, 125.7(Ar-C), 121.9(d, ³ J _{C, P} ＝4.4Hz, Ar-C), 121.8(d, ³ J _C,P ＝4.4Hz,Ar-C),94.3,94.2(C-5),88.7(d, ¹ J _C,F ＝172.5Hz,C-3'),83.5(d, ¹ J _C,F ＝165Hz,C-3'),79.8,79.7,79.6,79.4,79.3(C-2'),66.9(d, ¹ J _C,P ＝157.5Hz,CH ₂ P),66.7(d, ¹ J _{C ,P} ＝150.0Hz,CH ₂ P),66.5,66.4,65.7(OCH ₂ (CH ₂ ) ₃ CH ₃ ),51.5(C-1'),50.5(d, ² J _C,P ＝8.3Hz,C -α-Asp), 50.4(d, ² J _{C, P} ＝8.3Hz, C-α-Asp), 39.8(d, ³ J _{C, P} ＝4.2Hz, C-β-Asp), 39.6(d, ³ J _{C, P} ＝3.8Hz, C-β-Asp), 29.0, 28.9, 28.8, 28.7 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ),14.3(O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121 MHz, CD ₃ CN): δ 22.4, 21.7; HRMS for C ₂₈ H ₄₂ FN ₄ O ₈ P [MH] - calcd: 611.2651, found: 611.2655.

Example 37: (S)-O ² -{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}cytosine (27a)

According to the general procedure, from compound 19a (20 mg, 0.07 mmol), aspartate HCl salt (38 mg, 0.12 mmol), PhOH (30 mg, 0.32 mmol), Et ₃ N (0.10 mL, 0.70 mmol), 2,2 Starting with anhydrous pyridine (3 mL) of '-dithiobipyridine (110 mg, 0.50 mmol) and _PPh3 (130 mg, 0.50 mmol) afforded compound 27a (12 mg, 28%) as a colorless oil. The crude residue was purified by column chromatography on silica gel (gradient DCM/MeOH, 40:1, v/v; 30:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ7.95-7.93(m, 1H, H-6), 7.38-7.16(m, 5H, ArH), 6.19(s, 1H, H-5), 6.17( s,1H,H-5),5.61(s,2H,NH ₂ ),4.75-3.93(m,13H,H-3',H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.86-2.63(m,2H,H-β-Asp),1.64-1.52(m,4H,2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ), 1.34-1.27(m, 8H, 2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ), 0.93-0.87(m, 6H, 2x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz , CD ₃ CN): δ173.0(d, ³ J _{C, P} ＝4.4Hz, CO-α), 172.8(d, ³ J _{C, P} ＝4.5Hz, CO-α), 171.5 (CO-β) ,166.6(C-4),165.9(C-2),158.0(C-6),151.3(Ar-C),130.6(Ar-C),125.8(Ar-C),122.0(d, ³ J _{C ,P} ＝4.0Hz,Ar-C),121.9(d, ³ J _C,P ＝4.3Hz,Ar-C),100.6(C-5),83.9(d, ¹ J _C,F ＝168.0Hz,C -3'),82.7(d, ¹ J _C,F ＝168.0Hz,C-3'),80.1,80.0,79.9,79.7,79.6,79.5,79.3(C-2'),66.9(d, ¹ J _C,P ＝152.3Hz, CH ₂ P),66.7(d, ¹ J _C,P ＝150.0Hz,CH ₂ P),66.5,66.4,65.7,65.4,65.3,65.2(OCH ₂ (CH ₂ ) ₃ CH ₃ ,C-1'),51.7,51.5(C-α-Asp),39.8(d, ³ J _C,P ＝3.9Hz,C-β-Asp),39.6(d, ³ J _C,P ＝4.2 Hz, C-β-Asp), 29.0, 28.9, 28.8, 28.7 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 (O( CH ₂ ) ₄ CH ₃ ); ³¹ P N MR (121 MHz, CD ₃ CN): δ 22.5, 21.9; HRMS for C ₂₈ H ₄₂ FN ₄ O ₈ P [MH] - calcd: 611.2651, found: 611.2642.

Example 38: (R)-O ² -{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}cytosine (27b)

According to the general procedure, from compound 19b (60 mg, 0.21 mmol), aspartate HCl salt (114 mg, 0.36 mmol), PhOH (90 mg, 0.96 mmol), Et ₃ N (0.30 mL, 2.10 mmol), 2,2 Starting with anhydrous pyridine (5 mL) of '-dithiobipyridine (330 mg, 1.50 mmol) and _PPh3 (390 mg, 1.50 mmol), afforded compound 27b (31 mg, 24%) as a colorless oil. The crude residue was purified by column chromatography on silica gel (gradient DCM/MeOH, 40:1, v/v; 30:1, v/v). ¹ H NMR (300MHz, CD ₃ CN): δ7.94(s, 1H, H-6), 7.92(s, 1H, H-6), 7.39-7.19(m, 5H, ArH), 6.18(s, 1H,H-5),6.16(s,1H,H-5),5.73(s,2H,NH ₂ ),4.75-3.93(m,13H,H-3',H-2',H-1' ,2xOCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.86-2.59(m,2H,H-β-Asp),1.63-1.51(m,4H,2xOCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ),1.39-1.24(m,8H,2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ),0.95-0.87(m,6H,2x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.8, 172.7 (CO-α), 171.6, 171.5 (CO-β), 166.6 (C-4), 165.9 (C-2), 157.9 (C-6 ), 151.4(Ar-C), 130.6(Ar-C), 125.8, 125.7(Ar-C), 122.0(d, ³ J _{C, P} = 4.1Hz, Ar-C), 121.9(d, ³ J _{C ,P} ＝4.4Hz,Ar-C),100.7,100.6(C-5),83.8(d, ¹ J _C,F ＝165.0Hz,C-3'),80.2,80.0,79.9,79.7,79.6,79.5 ,79.3(C-2'),67.0(d, ¹ J _C,P ＝157.5Hz,CH ₂ P),66.6(d, ¹ J _C,P ＝150.0Hz,CH ₂ P),66.5,66.4,65.7 ,65.6(OCH ₂ (CH ₂ ) ₃ CH ₃ ),65.3(d, ³ J _C,F ＝7.5Hz,C-1'),51.5(C-α-Asp),39.8(d, ³ J _{C, P} ＝4.0Hz, C-β-Asp), 39.6(d, ³ J _{C, P} ＝3.9Hz, C-β-Asp), 29.0, 28.9, 28.8, 28.7 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 (O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121MHz, CD ₃ CN): δ22.8, 21.8; HRMS for C ₂₈ H ₄₂ FN ₄ O ₈ P [MH] - Calculated: 611.2651, Found: 611.2650.

Example 39: (S)-9-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}guanine (29a)

According to the general procedure, from compound 23a (30 mg, 0.09 mmol), aspartate HCl salt (50 mg, 0.16 mmol), PhOH (40 mg, 0.41 mmol), Et ₃ N (0.13 mL, 0.90 mmol), 2,2 Start with '-dithiobipyridine (145 mg, 0.65 mmol) and _PPh3 (170 mg, 0.65 mmol) in anhydrous pyridine (3 mL). The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 40:1, v/v; 30:1, v/v) to afford the triphosphine adduct of compound 29a. The collected eluent was evaporated and redissolved in _CH3CN / _H2O (1:1, v/v, 10 mL). 1 drop of 1M HCl solution was added at 0°C, and the mixture was stirred at room temperature for another 1 hour. The solution was neutralized with 2M TEAB. After removal of all volatiles, the resulting residue was purified by RP-HPLC (CH ₃ CN, H ₂ O) to afford compound 29a (3 mg, 5%) as a colorless oil. ¹ H NMR (300MHz, CD ₃ CN): δ7.64(s, 1H, H-8), 7.61(s, 1H, H-8), 7.38-7.13(m, 5H, ArH), 4.74-3.92( m,13H,H-3',H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.82-2.54(m,2H, H-β-Asp), 1.61-1.52(m, 4H, 2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ), 1.33-1.26(m, 8H, 2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ),0.92-0.85(m,6H,O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR(75MHz,CD ₃ CN):δ172.8,172.7(CO-α),171.6,171.5(CO-β), 154.7, 154.6(C-2), 152.8(C-4), 151.2(Ar-C), 139.3(C-8), 130.6(Ar-C), 125.9, 125.8(Ar-C), 121.9(d, ³ J _{C, P} = 4.3Hz, Ar-C), 121.7 (d, ³ J _{C, P} = 4.4Hz, Ar-C), 118.3 (C-5, overlapping with CD ₃ CN), 83.5 (d, ¹ J _C,F ＝172.5Hz,C-3'),83.2(d, ¹ J _C,F ＝165.0Hz,C-3'),79.7,79.6,79.5(C-2'),66.7(d, ¹ J _C,P ＝157.5Hz, CH ₂ P), 66.6, 66.5, 65.8, 65.7 (OCH ₂ (CH ₂ ) ₃ CH ₃ ), 51.6, 51.5 (C-1'), 43.8 (C-α-Asp) , 39.8, 39.6 (C-β-Asp), 29.0, 28.9, 28.8, 28.7 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 (O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121 MHz, CD ₃ CN): δ 22.3, 21.5; HRMS for C ₂₉ H ₄₂ FN ₆ O ₈ P[MH] - calcd: 651.2713, found : 651.2733.

Example 40: (R)-9-{3-Fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy] Propyl}guanine (29b)

According to the general procedure, from compound 23b (60 mg, 0.18 mmol), aspartate HCl salt (100 mg, 0.32 mmol), PhOH (80 mg, 0.82 mmol), Et ₃ N (0.26 mL, 1.80 mmol), 2,2 Start with '-dithiobipyridine (290 mg, 1.30 mmol) and _PPh3 (340 mg, 1.30 mmol) in anhydrous pyridine (5 mL). The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 40:1, v/v; 30:1, v/v) to afford the triphosphine adduct of compound 28b. The collected eluent was evaporated and redissolved in _CH3CN / _H2O (1:1, v/v, 10 mL). 1 drop of 1M HCl solution was added at 0°C, and the mixture was stirred at room temperature for another 1 hour. The solution was neutralized with 2M TEAB. After removal of all volatiles, the resulting residue was purified by RP-HPLC (CH ₃ CN, H ₂ O) to afford compound 29b (5 mg, 4%) as a colorless oil. ¹ H NMR (300MHz, CD ₃ CN): δ7.67(s, 1H, H-8), 7.65(s, 1H, H-8), 7.38-7.09(m, 5H, ArH), 4.76-3.94( m,13H,H-3',H-2',H-1',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ,H-α-Asp,NHPO),2.81-2.56(m,2H, H-β-Asp), 1.59-1.52(m, 4H, 2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ), 1.32-1.28(m, 8H, 2x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ), 0.92-0.86 (m, 6H, 2x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.8(CO-α), 171.6(CO-β), 158.6 (C-6), 154.6(C-2), 152.7(C-4), 151.4(Ar-C), 139.3(C-8), 130.7, 130.6(Ar-C), 125.9(Ar-C), 121.8 (t, ³ J _{C, P} = 4.7Hz, Ar-C), 118.3 (C-5, overlapping with CD ₃ CN), 83.4 (d, ¹ J _{C, F} = 172.5Hz, C-3'), 83.2(d, ¹ J _C,F ＝165.0Hz,C-3'),79.8,79.6,79.5,79.4(C-2'),66.9(d, ¹ J _C,P ＝150.0Hz,CH ₂ P) ,66.6(d, ¹ J _C,P ＝157.5Hz,CH ₂ P),66.5,65.8(OCH ₂ (CH ₂ ) ₃ CH ₃ ),51.5(C-1'),43.8(C-α-Asp) , 39.8, 39.6 (C-β-Asp), 29.0, 28.9, 28.8, 28.7 (OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.0, 22.9 (O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 (O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121 MHz, CD ₃ CN): δ 22.3, 21.7; HRMS for C ₂₉ H ₄₂ FN ₆ O ₈ P[MH] ^- calcd: 651.2726, found : 651.2733.

Example 41: (R)-2-Amino-6-chloro-9-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}purine (31a)

A solution of DIAD (0.24 mL, 1.20 mmol) in anhydrous THF (1 mL) was added dropwise to 30 (120 mg, 0.74 mmol), 4a (150 mg, 0.61 mmol) and Ph ₃ P (300 mg, 1.20 mmol) at room temperature in a mixture of anhydrous THF (5 mL). The reaction mixture was stirred for 24 hours, then _H2O (5 mL) was added. The resulting mixture was refluxed for 24 hours (to remove the triphenylphosphine adduct). After removal of all volatiles, the crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 50:1, v/v; 30:1, v/v; 25:1, v/v) to give colorless 31a as an oil (200 mg, 83%). ¹ H NMR (300MHz, CDCl ₃ ): δ7.91(s,1H,H-8),5.50(s,1H,NH ₂ ),4.71-4.35(m,3H,H-3',H-1' a), 4.26-3.92 (m, 7H, H-1'b, H-2', 2x CH ₂ CH ₃ , PCH ₂ a), 3.83 (dd, J＝13.9, 8.8Hz, 1H, PCH ₂ b) , 1.35-1.26 (m, 6H, 2xCH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ159.5 (C-2), 154.1 (C-4), 151.5 (C-6), 143.5 ( C-8),125.1(C-5),82.0(d, ¹ J _C,P ＝173.9Hz,C-3'),78.4(dd, ² J _C,F ＝19.5Hz, ³ J _C,P ＝ 9.6Hz,C-2'),64.7(d, ¹ J _C,P ＝167.1Hz,CH ₂ P),62.9,62.8(CH ₂ CH ₃ ),43.8(d, ³ J _C,F ＝8.0Hz, C-1'), 16.7, 16.6 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ20.5; HRMS calculated for C ₁₃ H ₂₀ ClFN ₅ O ₄ P[M+H] ⁺ : 396.0998, found value: 396.1002.

Example 42: 3.2.2(S)-2-Amino-6-chloro-9-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}purine (31b)

From 30 (250 mg, 1.47 mmol), 4b (300 mg, 1.47 mmol), _Ph3P (640 mg, 2.46 mmol) and DIAD (0.48 mL, 2.46 mmol) in dry THF (10 mL) according to the procedure used for the preparation of 31a The solution started to give compound 31b (300 mg, 70%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 50:1, v/v; 30:1, v/v; 25:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ7.90(s,1H,H-8),5.40(s,1H,NH ₂ ),4.71-4.34(m,3H,H-3',H-1' a), 4.25-3.79 (m, 8H, H-1'b, H-2', 2x CH ₂ ^CH ₃ , PCH ₂ ), 1.35-1.24 (m, 6H, 2x CH ₂ CH ₃ ); (75MHz, CDCl ₃ ): δ159.5(C-2), 154.2(C-4), 151.5(C-6), 143.6(C-8), 125.1(C-5), 82.0(d, ¹ J _C,P ＝173.7Hz,C-3'),78.4(dd, ² J _C,F ＝19.7Hz, ³ J _C,P ＝9.5Hz,C-2'),64.8(d, ¹ J _C,P ＝167.0Hz, CH ₂ P), 62.9, 62.8 (CH ₂ CH ₃ ), 43.8 (d, ³ J _{C, F} ＝7.8Hz, C-1'), 16.7, 16.6 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ 20.5; HRMS calcd for C ₁₃ H ₂₀ ClFN ₅ O ₄ P [M+H] ⁺ : 396.0998, found: 396.0998.

Example 43: (R)-2-Amino-6-(4-methoxyphenylthio)-9-{2-[(diethylphosphoryl)methoxy]-3-fluoropropyl} Purine (32a)

4-Methoxythiophenol (0.12 mL, 0.96 mmol) was added to a mixture of 31a (190 mg, 0.48 mmol) and triethylamine (0.07 mL, 0.48 mmol) in anhydrous DMF (10 mL) at room temperature , and the mixture was stirred at 100 °C for another 4 hours. The solution was diluted with EtOAc (100 mL) and washed with saturated aqueous NaHCO ₃ (50 mL) and brine (50 mL). The organic layer was dried over _Na2SO4 , filtered and concentrated _under reduced pressure. The residue was then purified by silica gel column chromatography (gradient DCM/MeOH, 60:1, v/v; 50:1, v/v; 40:1, v/v) to afford 32a as a colorless oil ( 210mg, 87%). ¹ H NMR (600MHz, CDCl ₃ ): δ7.76(s, 1H, H-8), 7.52(d, J=8.9Hz, 2H, ArH), 6.94(d, J=8.9Hz, 2H, ArH) ,4.88(s,2H,NH ₂ ),4.64-4.38(m,2H,H-3'),4.33-4.28(m,1H,H-1'a),4.19-4.04(m,6H,H- 1'b, H-2', 2x CH ₂ CH ₃ ), 3.91 (dd, J=13.9, 8.7Hz, 1H, PCH ₂ a), 3.85-3.77 (m, 4H, OCH ₃ , PCH ₂ b), 1.34-1.27 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (150MHz, CDCl ₃ ): δ161.7 (C-2), 160.4 (Ar-C), 159.1 (C-6), 150.9 ( C-4), 141.0(C-8), 137.1(Ar-C), 124.6(C-5), 118.0(Ar-C), 114.5(Ar-C), 82.0(d, ¹ J _{C, P} = 173.6Hz,C-3'),78.3(dd, ² J _C,F ＝19.2Hz, ³ J _C,P ＝9.9Hz,C-2'),64.5(d, ¹ J _C,P ＝166.9Hz, CH ₂ P), 62.5, 62.4 (d, ² J _{C, P} = 6.4Hz, CH ₂ CH ₃ ), 55.3 (OCH ₃ ), 43.1 (d, ³ J _{C, F} = 7.9Hz, C-1') , 16.4, _16.3 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ 19.9; HRMS calcd for C ₂₀ H ₂₇ FN 5 O ₅ PS [M+H] ⁺ : 500.1527, found: 500.1526.

Example 44: (S)-2-Amino-6-(4-methoxyphenylthio)-9-{2-[(diethylphosphoryl)methoxyl]-3-fluoropropyl }purine (32b)

From 31b (190 mg, 0.48 mmol), 4-methoxythiophenol (0.12 mL, 0.96 mmol) and triethylamine (0.07 mL, 0.48 mmol) in anhydrous DMF (10 mL) according to the procedure for the preparation of 32a Initially, compound 32b (160 mg, 67%) was obtained as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 60:1, v/v; 50:1, v/v; 40:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ7.77(s, 1H, H-8), 7.53(d, J=8.8Hz, 2H, ArH), 6.95(d, J=8.8Hz, 2H, ArH) ,5.03(s,1H,NH ₂ ),4.70-4.30(m,3H,H-3',H-1'a),4.22-3.98(m,6H,H-1'b,H-2', 2x CH ₂ CH ₃ ), 3.93-3.77 (m, 5H, PCH ₂ , OCH ₃ ), 1.35-1.26 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ CNMR (75MHz, CDCl ₃ ): δ162.1 ( C-2), 160.9(Ar-C), 159.0(C-6), 151.0(C-4), 141.7(C-8), 137.5(Ar-C), 124.9(C-5), 118.0(Ar -C),115.0(Ar-C),82.3(d, ¹ J _C,P ＝173.7Hz,C-3'),78.7(dd, ² J _C,F ＝19.5Hz, ³ J _C,P ＝9.9 Hz,C-2'),64.9(d, ¹ J _C,P ＝166.9Hz,CH ₂ P),62.9,62.8(CH ₂ CH ₃ ),55.6(OCH ₃ ),43.6(d, ³ J _{C, F} = 8.1Hz, C-1'), 16.8, 16.7 (CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ20.5; HRMS for C ₂₀ H ₂₇ FN ₅ O ₅ PS [M+H ] ⁺ Calculated: 500.1527, Found: 500.1518.

Example 45: 4-Chloro-5-fluoro-2-pivaloylamino-7H-pyrrolo[2,3-d]pyrimidine (35)

4-Chloro-2-pivaloylamino-7H-pyrrolo[2,3-d]pyrimidine 34 (150 mg, 0.59 mmol) and selective fluorine reagent (320 mg, 0.90 mmol) were placed in a round bottom flask, then Anhydrous MeCN (6 mL) and AcOH (0.6 mL) were added. Then, the mixture was heated at 50 °C for 30 min under _N2 . Then, the mixture _was cooled with ice water and diluted with _CH2Cl2 (50 mL). The organic layer was washed with saturated NaHCO ₃ (50 mL). The inorganic layer was separated and extracted with _CH2Cl2 ( _2x20ml ). The combined organic layers were dried over _Na2SO4 , filtered and concentrated _under reduced pressure. The residue was then purified by silica gel column chromatography (gradient DCM/MeOH, 200:1) to afford 35 (48 mg, 30%) as a colorless foam. ¹ H NMR (300MHz, CDCl ₃ ): δ11.79 (s, 1H, NHCO), 8.25 (s, 1H, H-6), 1.39 (s, 9H, (CH ₃ ) ₃ C); ¹³ C NMR ( 75MHz, CDCl ₃ ): 176.5(NHCO), 151.3(C-2), 150.8(C-4), 147.8(C-7a), 141.4(d, ¹ J _{C, F} ＝248.8Hz, C-5), 111.2(d, ² J _C,F ＝26.0Hz,C-6),103.6(d, ² J _C,F ＝14.9Hz,C-4a),40.5(C(CH ₃ ) ₃ ),27.7(C( CH ₃ ) ₃ ).

Example 46: (R)-4-Chloro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-2-pivaloylamino-7H-pyrrolo[ 2,3-d] pyrimidine (36a)

A solution of DIAD (0.24 mL, 1.20 mmol) in anhydrous THF (1 mL) was added dropwise to 34 (180 mg, 0.74 mmol), 4a (150 mg, 0.61 mmol) and Ph ₃ P (300 mg, 1.20 mmol) at room temperature in a mixture of anhydrous THF (10 mL). The reaction mixture was stirred for 24 hours, then it was concentrated under reduced pressure. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 60:1, v/v; 40:1, v/v; 30:1, v/v) to give 36a (220 mg ,78%). ¹ H NMR (300MHz, CDCl ₃ ): δ8.16 (s, 1H, NHCO), 7.29 (dd, J = 0.9Hz, 1H, H-6), 6.53 (dd, J = 3.6, 0.9Hz, 1H, H-6),4.74-4.31(m,4H,H-3',H-1'),4.18-3.86(m,7H,H-2',2x CH ₂ CH ₃ ,PCH ₂ ),1.36-1.27 (m, 15H, (CH ₃ ) ₃ C, 2x CH ₂ CH ₃ ); ¹³ C NMR (150MHz, CDCl ₃ ): δ175.7 (NHCO), 152.3 (C-4, C-7a), 151.6 (C -2),130.1(C-6),114.2(C-4a),100.1(C-5),82.9(d, ¹ J _C,P ＝173.2Hz,C-3'),79.4(dd, ² J _C,F ＝19.1Hz, ³ J _C,P ＝10.9Hz,C-2'),64.9(d, ¹ J _C,P ＝166.9Hz,CH ₂ P),62.7,62.6(CH ₂ CH ₃ ), ³¹ _{_ _ _ _ _ _ _} ^_ P NMR (121 MHz, _CDCl3 ) _: δ20.9; _HRMS calcd for _{C19H29ClFN4O5P} [M+H] ⁺ _: 479.1621, found: 479.1617.

Example 47: (S)-4-Chloro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-2-pivaloylamino-7H-pyrrolo[ 2,3-d] pyrimidine (36b)

From 34 (180 mg, 0.74 mmol), 4b (230 mg, 1.47 mmol), _Ph3P (300 mg, 1.20 mmol) and DIAD (0.24 mL, 1.20 mmol) in anhydrous THF (10 mL) according to the procedure used for the preparation of 36a The solution started to give compound 36b (230 mg, 79%) as a colorless oil. The crude residue was purified by column chromatography on silica gel (gradient DCM/MeOH, 60:1, v/v; 40:1, v/v; 30:1, v/v). ¹ H NMR (600MHz, CDCl ₃ ): δ8.13(s, 1H, NHCO), 7.30(dd, J=3.6, 2.0Hz, 1H, H-6), 6.53(dd, J=3.6, 2.5Hz, 1H,H-6),4.69-4.59(m,1H,H-3'a),4.55-4.51(m,H-1'a),4.46-4.33(m,2H,H-3'b,H -1'b),4.15-4.08(m,5H,H-2',2x CH ₂ CH ₃ ),4.00-3.96(m,1H,PCH ₂ a),3.92-3.88(m,1H,PCH ₂ b ), 1.35-1.29 (m, 15H, (CH ₃ ) ₃ C, 2x CH ₂ CH ₃ ); ¹³ C NMR (150MHz, CDCl ₃ ): δ175.5 (NHCO), 152.1 (C-4, C-7a ), 151.3(C-2), 129.8(C-6), 113.9(C-4a), 99.8(C-5), 82.5(d, ¹ J _{C, P} = 173.0Hz, C-3'), 79.1 (dd, ² J _C,F ＝19.0Hz, ³ J _C,P ＝11.1Hz,C-2'),64.5(d, ¹ J _C,P ＝167.2Hz,CH ₂ P),62.5,62.4(CH ₂ CH ₃ ), 44.5(d, ³ J _{C, F} ＝8.5Hz, C-1'), 40.2(C(CH ₃ ) ₃ ), 27.4(C(CH ₃ ) ₃ ), 16.4(CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ 20.9; HRMS calcd for C ₁₉ H ₂₉ ClFN ₄ O ₅ P[M+H] ⁺ : 479.1621, found: 479.1624.

Example 48: (R)-4-Chloro-5-fluoro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-2-pivaloylamino-7H -pyrrolo[2,3-d]pyrimidine (37a)

From 35 (200 mg, 0.74 mmol), 4a (150 mg, 0.61 mmol), _Ph3P (300 mg, 1.20 mmol) and DIAD (0.24 mL, 1.20 mmol) in anhydrous THF (10 mL) according to the procedure used for the preparation of 36a The solution started to give compound 37a (70 mg, 25%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 80:1, v/v; 60:1, v/v; 40:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.13 (s, 1H, NHCO), 7.10 (d, J=2.6Hz, 1H, H-6), 4.72-3.96 (m, 9H, H-3', H-1',H-2',2x CH ₂ CH ₃ ),4.00(dd,J＝13.8,8.7Hz,1H,PCH ₂ a),3.88(dd,J＝13.8,9.2Hz,1H,PCH ₂ b), 1.34-1.28(m, 15H, (CH ₃ ) ₃ C, 2x CH ₂ CH ₃ ); ¹³ CNMR (125MHz, CDCl ₃ ): δ175.6(NHCO), 152.0(C-2), 150.9( d, ³ J _C,F ＝4.2Hz,C-4),147.9(C-7a),141.6(d, ¹ J _C,F ＝252.5Hz,C-5),112.5(d, ² J _C,F ＝26.5Hz, C-6), 103.6(d, ² J _{C, F} ＝14.9Hz, C-4a), 82.6(d, ¹ J _{C, P} ＝173.3Hz, C-3'), 79.5, 79.4, 79.2, 79.1(C-2'), 64.8(d, ¹ J _{C, P} ＝166.9Hz, CH ₂ P), 62.7, 62.6(CH ₂ CH ₃ ), 44.4(d, ³ J _{C, F} ＝8.5Hz ,C-1'),40.5(C(CH ₃ ) ₃ ),27.6(C(CH ₃ ) ₃ ),16.6,16.5(CH ₂ CH ₃ ); ³¹ P NMR(121MHz,CDCl ₃ ):δ20.9 ; _HRMS calcd for _{C19H28ClF2N4O5P} [M+H] ⁺ : _497.1527 , _{found :} 497.1523.

Example 49: (S)-4-Chloro-5-fluoro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-2-pivaloylamino-7H -pyrrolo[2,3-d]pyrimidine (37b)

From 35 (200 mg, 0.74 mmol), 4b (100 mg, 1.47 mmol), _Ph3P (300 mg, 1.20 mmol) and DIAD (0.24 mL, 1.20 mmol) in dry THF (10 mL) according to the procedure used for the preparation of 36a The solution started to give compound 37b (100 mg, 33%) as a colorless oil. The crude residue was purified by column chromatography on silica gel (gradient DCM/MeOH, 80:1, v/v; 60:1, v/v; 40:1, v/v). ¹ H NMR (600MHz, CDCl ₃ ): δ8.13(s, 1H, NHCO), 7.10(d, J=2.5Hz, 1H, H-6), 4.67-4.25(m, 4H, H-3', H-1'), 4.18-4.02(m, 5H, H-2', 2x CH ₂ CH ₃ ), 4.00(dd, J=13.8, 8.7Hz, 1H, PCH ₂ a), 3.89(dd, J= 13.8, 9.2Hz, 1H, PCH ₂ b), 1.34-1.30 (m, 15H, (CH ₃ ) ₃ C, 2x CH ₂ CH ₃ ); ¹³ C NMR (125MHz, CDCl ₃ ): δ175.5 (NHCO) ,151.8(C-2),150.7(C-4),147.6(C-7a),141.3(d, ¹ J _C,F ＝252.3Hz,C-5),112.4(d, ² J _C,F ＝ 26.3Hz, C-6), 103.4(d, ² J _{C, F} ＝14.9Hz, C-4a), 82.4(d, ¹ J _{C, P} ＝173.3Hz, C-3'), 79.2, 79.0 (C -2'),64.5(d, ¹ J _C,P ＝167.0Hz,CH ₂ P),62.5(CH ₂ CH ₃ ),44.1(d, ³ J _C,F ＝8.5Hz,C-1'), 40.3 (C(CH ₃ ) ₃ ), 27.4 (C(CH ₃ ) ₃ ), 16.4 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ 20.8; HRMS for C ₁₉ H ₂₈ ClF ₂ Calcd _{for N4O5P} [M+H] ⁺ : 497.1527, found: 497.1521.

Example 50: (R)-2-Amino-3,4-dihydro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-7H-pyrrolo[ 2,3-d]pyrimidin-4-one (38a)

A mixture of 36a (200 mg, 0.42 mmol), DABCO (46 mg, 0.42 mmol) and K ₂ CO ₃ (58 mg, 0.42 mmol) in dioxane and H ₂ O (6 mL, 5:1, v/v) was solvent The mixture in was stirred at 90°C for 3 hours. The reaction was then concentrated under reduced pressure to give a residue which was redissolved in 30% methanolic ammonia (20 mL) and stirred at room temperature for 12 hours. After removal of all volatiles, the residue was purified by silica gel column chromatography (gradient DCM/MeOH, 20:1, v/v; 15:1, v/v; 10:1, v/v) to give a colorless oil 38a (100 mg, 64%) in the form of a compound. ¹ H NMR (300MHz, CDCl ₃ ): δ11.01(s, 1H, NHCO), 6.59(dd, J=3.5, 0.9Hz, 1H, H-6), 6.50(dd, J=3.5, 0.9Hz, 1H,H-5),6.23(s,2H,NH ₂ ),4.67-4.28(m,2H,H-3'),4.23-4.10(m,6H,H-1',2x CH ₂ CH ₃ ) _{13 C NMR _} ^_ (75MHz, CDCl ₃ ): δ160.7(C-4), 152.8(C-2), 151.1(C-7a), 121.6(C-6), 102.6(C-4a), 101.3(C-5) ,82.2(d, ¹ J _C,P ＝173.4Hz,C-3'),79.6(dd, ² J _C,F ＝18.7Hz, ³ J _C,P ＝11.5Hz,C-2'),64.7( d, ¹ J _{C, P} ＝168.3Hz, CH ₂ P), 62.3, 62.2 (CH ₂ CH ₃ ), 44.5 (d, ³ J _{C, F} ＝8.0Hz, C-1'), 16.7, 16.6 (CH ₂ CH ₃ ); ³¹ PNMR (121 MHz, CDCl ₃ ): δ 21.0; HRMS calcd for C ₁₄ H ₂₂ FN ₄ O ₅ P[M+H] ⁺ : 377.1384, found: 377.1387.

Example 51: (S)-2-Amino-3,4-dihydro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-7H-pyrrolo[ 2,3-d]pyrimidin-4-one (38b)

From 36b (100 mg, 0.21 mmol) in a solvent mixture of dioxane and H ₂ O (6 mL, 5:1, v/v) and NH ₃ /MeOH (20 mL), according to the procedure for the preparation of 38a, Starting with DABCO (23 mg, 0.21 mmol) and K ₂ CO ₃ (29 mg, 0.21 mmol) afforded compound 38b (50 mg, 64%) as a colorless oil. The crude residue was purified by column chromatography on silica gel (gradient DCM/MeOH, 20:1, v/v; 15:1, v/v; 10:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ11.04(s, 1H, NHCO), 6.60(d, J=3.4Hz, 1H, H-6), 6.49(d, J=3.5Hz, 1H, H- 5),6.21(s,2H,NH ₂ ),4.67-4.29(m,2H,H-3'),4.22-4.11(m,6H,H-1',2x CH ₂ CH ₃ ),4.04-3.93 (m, 2H, H-2', PCH ₂ a), 3.86-3.78 (m, 1H, PCH ₂ b), 1.36-1.30 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ160.6(C-4), 152.7(C-2), 150.7(C-7a), 121.6(C-6), 102.6(C-4a), 101.2(C-5), 82.2(d , ¹ J _C,P ＝173.6Hz,C-3'),79.6(C-2'),64.7(d, ¹ J _C,P ＝168.3Hz,CH ₂ P),62.3,62.2(CH ₂ CH ₃ ), 44.6 (d, ³ J _{C, F} = 8.0Hz, C-1'), 16.7, 16.6 (CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ21.0; HRMS for C ₁₄ H ₂₂ FN ₄ O ₅ P [M+H] ⁺ Calc.: 377.1384, Found: 377.1384.

Example 52: (R)-2-Amino-5-fluoro-3,4-dihydro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-7H -pyrrolo[2,3-d]pyrimidin-4-one (39a)

According to the procedure used for the preparation of 38a, from 37a (60 mg, 0.12 mmol), DABCO (14 mg, 0.12 mmol) and K ₂ CO ₃ (17 mg, 0.12 mmol) in dioxane and H ₂ O (6 mL, 5:1 , v/v) and a mixture solvent of NH ₃ /MeOH (20 mL) afforded compound 39a (20 mg, 30%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 18:1, v/v; 15:1, v/v; 10:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ6.42 (d, J=2.3Hz, 1H, H-6), 5.99 (s, 2H, NH ₂ ), 4.66-3.83 (m, 11H, H-3' , H-1', H-2', 2x CH ₂ CH ₃ , PCH ₂ ), 1.37-1.32 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ158.4 ( d, ² J _C,F ＝2.6Hz,C-4),152.3(C-2),146.7(C-7a),145.4(d, ¹ J _C,F ＝248.6Hz,C-5),103.6( d, ² J _C,F ＝26.7Hz,C-6),90.6(d, ² J _C,F ＝13.9Hz,C-4a),81.9(d, ¹ J _C,P ＝173.2Hz,C-3 '),79.0(dd, ² J _C,F ＝19.0Hz, ³ J _C,P ＝10.8Hz,C-2'),64.2(d, ¹ J _C,P ＝167.5Hz,CH ₂ P),62.4 , 62.3 (CH ₂ CH ₃ ), 43.5 (d, ³ J _{C, F} ＝7.9Hz, C-1'), 16.1, 16.0 (CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ20. 3; HRMS _calcd for _{C14H21F2N4O5P} [M+H] ⁺ : _395.1290 , _{found :} 395.1284.

Example 53: (S)-2-Amino-5-fluoro-3,4-dihydro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-7H -pyrrolo[2,3-d]pyrimidin-4-one (39b)

From 37b (90 mg, 0.18 mmol) in a solvent mixture of dioxane and H ₂ O (6 mL, 5:1, v/v) and NH ₃ /MeOH (20 mL), according to the procedure for the preparation of 38a, Starting with DABCO (20 mg, 0.18 mmol) and K ₂ CO ₃ (25 mg, 0.18 mmol) afforded compound 39b (25 mg, 35%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 18:1, v/v; 15:1, v/v; 10:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ6.41 (d, J=2.4Hz, 1H, H-6), 6.00 (s, 2H, NH ₂ ), 4.66-3.82 (m, 11H, H-3' , H-1', H-2', 2x CH ₂ CH ₃ , PCH ₂ ), 1.36-1.31 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ159.0( C-4),152.9(C-2),147.3(C-7a),146.1(d, ¹ J _C,F ＝248.6Hz,C-5),104.2(d, ² J _C,F ＝26.5Hz, C-6),91.2(d, ² J _C,F ＝13.7Hz,C-4a),82.5(d, ¹ J _C,P ＝173.1Hz,C-3'),79.6(dd, ² J _{C, F} ＝19.2Hz, ³ J _C,P ＝11.1Hz,C-2'),64.8(d, ¹ J _C,P ＝167.6Hz,CH ₂ P),63.0,62.9(CH ₂ CH ₃ ),44.2( d, ³ J _C,F = 7.9Hz, C-1'), 16.7, 16.6 (CH ₂ CH ₃ ); ³¹ P NMR (121MHz, CDCl ₃ ): δ20.9; HRMS for C ₁₄ H ₂₁ F ₂ N ₄ O ₅ P [M+H] ⁺ Calcd: 395.1290, Found: 395.1286.

Example 54: 4-Chloro-5-cyano-2-pivaloylamino-7H-pyrrolo[2,3-d]pyrimidine (46)

5-Cyano-3,4-dihydro-2-pivaloylamino-7H-pyrrolo[2,3-d] in dry MeCN (3 mL) was treated dropwise with POCl ₃ (2.95 g, 19.30 mmol) Pyrimidin-4-one 45 (500 mg, 1.93 mmol), N,N-dimethylaniline (980 mg, 8.10 mmol) and triethylbenzyl ammonium chloride (220 mg, 0.96 mmol). The reaction mixture was refluxed for 1 hour, allowed to cool and concentrated in vacuo. The resulting black oil was carefully treated with ice and brought to pH=5 using 33% ammonia in _H2O . The aqueous layer was extracted with EtOAc (2 x 50 mL). The combined organic layers were dried over _Na2SO4 , filtered and concentrated _under reduced pressure. The residue was then purified by silica gel column chromatography (gradient: hexane:EtOAc, 3:1, v/v; 1:1, v/v) to afford 46 (350 mg, 65%) as a white powder. ¹ H NMR (300MHz, CDCl ₃ ): δ10.30(s, 1H, NHCO), 8.52(s, 1H, H-6), 1.24(s, 9H, (CH ₃ ) ₃ C); ¹³ C NMR ( 75MHz, CDCl ₃ ): δ176.0 (NHCO), 153.2, 152.9, 150.8 (C-4, C-7a, C-2), 137.7 (C-6), 114.6 (C-5), 111.3 (C- 4a), 83.5 (CN), 40.5-38.8 (C(CH ₃ ) ₃ , overlapping with DMSO), 26.9 (C(CH ₃ ) ₃ ).

Example 55: (R)-4-Chloro-5-cyano-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-2-pivaloylamino- 7H-pyrrolo[2,3-d]pyrimidine (47a)

From 46 (150 mg, 0.54 mmol), 4a (120 mg, 0.49 mmol), _Ph3P (260 mg, 0.98 mmol) and DIAD (0.19 mL, 0.98 mmol) in anhydrous THF (10 mL) according to the procedure used for the preparation of 36a The solution started to give compound 47a (220 mg, 80%) as a colorless oil. The crude residue was purified by silica gel column chromatography (gradient DCM/MeOH, 50:1, v/v; 40:1, v/v; 30:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.24(s,1H,NHCO),7.91(s,1H,H-6),4.74-4.29(m,4H,H-3',H-1') ,4.17-3.96(m,6H,H-2',2x CH ₂ CH ₃ ,PCH ₂ a),3.81(dd,J＝13.9,9.0Hz,1H,PCH ₂ b),1.34-1.25(m,15H , (CH ₃ ) ₃ C, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ175.8 (NHCO), 153.4, 153.2, 152.3 (C-4, C-7a, C-2) ,138.2(C-6),113.5(C-5),112.1(C-4a),86.0(CN),82.3(d, ¹ J _C,P ＝174.0Hz,C-3'),78.7(dd, ² J _C,F ＝19.2Hz, ³ J _C,P ＝9.8Hz,C-2'),64.7(d, ¹ J _C,P ＝167.1Hz,CH ₂ P),62.9,62.8(CH ₂ CH ₃ ), 45.6(d, ³ J _{C, F} ＝8.4Hz, C-1'), 40.6(C(CH ₃ ) ₃ ), 27.6(C(CH ₃ ) ₃ ), 16.7(CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, _{CDCl3 )} : δ20.7; HRMS calcd for _{C20H28ClFN5O5P} [M+H] ⁺ _{: 504.1573} , found: 504.1567.

Example 56: (S)-4-Chloro-5-cyano-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}-2-pivaloylamino- 7H-pyrrolo[2,3-d]pyrimidine (47b)

From 46 (150 mg, 0.54 mmol), 4b (120 mg, 0.49 mmol), _Ph3P (260 mg, 0.98 mmol) and DIAD (0.19 mL, 0.98 mmol) in anhydrous THF (10 mL) according to the procedure used for the preparation of 36a The solution started to give compound 47b (150 mg, 60%) as a colorless oil. The crude residue was purified by column chromatography on silica gel (gradient DCM/MeOH, 50:1, v/v; 40:1, v/v; 30:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ8.24(s,1H,NHCO),7.92(s,1H,H-6),4.74-4.30(m,4H,H-3',H-1') ,4.15-3.96(m,6H,H-2',2x CH ₂ CH ₃ ,PCH ₂ a),3.81(dd,J＝13.9,9.0Hz,1H,PCH ₂ b),1.35-1.26(m,15H , (CH ₃ ) ₃ C, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ175.7 (NHCO), 153.2, 153.0, 152.1 (C-4, C-7a, C-2) ,138.1(C-6),113.4(C-5),111.9(C-4a),85.8(CN),82.1(d, ¹ J _C,P ＝174.0Hz,C-3'),78.5(dd, ² J _C,F ＝19.2Hz, ³ J _C,P ＝9.9Hz,C-2'),64.5(d, ¹ J _C,P ＝167.0Hz,CH ₂ P),62.8-62.6(CH ₂ CH ₃ ), 45.4(d, ³ J _{C, F} ＝8.6Hz, C-1'), 40.5(C(CH ₃ ) ₃ ), 27.5(C(CH ₃ ) ₃ ), 16.6, 16.5(CH ₂ CH ₃ ) ; ³¹ P NMR (121 MHz, CDCl ₃ ): δ 20.7; HRMS calcd for C ₂₀ H ₂₈ ClFN ₅ O ₅ P [M+H] ⁺ : 504.1573, found: 504.1578.

Example 57: (R)-2-Amino-5-cyano-3,4-dihydro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}- 7H-Pyrrolo[2,3-d]pyrimidin-4-one (48a)

From 47a (220 mg, 0.44 mmol) in a solvent mixture of dioxane and H ₂ O (6 mL, 5:1, v/v) and NH ₃ /MeOH (20 mL), according to the procedure for the preparation of 38a, Starting with DABCO (33 mg, 0.30 mmol) and K ₂ CO ₃ (61 mg, 0.44 mmol) afforded compound 48a (50 mg, 30%) as a colorless oil. The residue was purified by silica gel column chromatography (gradient DCM/MeOH, 20:1, v/v; 15:1, v/v; 10:1, v/v). ¹ H NMR (300MHz, CDCl ₃ ): δ10.89 (s, 1H, NHCO), 7.30 (d, J=1.1Hz, 1H, H-6), 6.16 (s, 2H, NH ₂ ), 4.71-4.29 (m,3H,H-3',H-1'a),4.21-3.93(m,7H,H-1'b,H-2',2x CH ₂ CH ₃ ,PCH ₂ a),3.83(dd , J=13.8, 9.1Hz, 1H, PCH ₂ b), 1.38-1.32 (m, 6H, 2x CH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ159.2(C-4), 154.0 (C-2), 152.2(C-7a), 130.9(C-6), 115.5(C-5), 99.6(C-4a), 86.7(CN), 82.4(d, ¹ J _{C, P} = 173.6 Hz,C-3'),79.1(dd, ² J _C,F ＝19.1Hz, ³ J _C,P ＝10.4Hz,C-2'),64.8(d, ¹ J _C,P ＝167.7Hz,CH ₂ P), 62.9, 62.8 (CH ₂ CH ₃ ), 45.2 (d, ³ J _{C, F} = 8.1 Hz, C-1'), 16.8, 16.7 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ 20.7; _{HRMS calcd} for _C15H21FN5O5P [M+H] ⁺ : _402.1336 , found: 402.1324.

Example 58: (S)-2-Amino-5-cyano-3,4-dihydro-7-{2-[(diethylphosphoryl)-methoxy]-3-fluoropropyl}- 7H-pyrrolo[2,3-d]pyrimidin-4-one (48b)

A mixture of 47b (150 mg, 0.30 mmol), _Et3N (0.12 mL, 0.89 mmol), NaOAc (73 mg, 0.89 mmol) and DABCO (33 mg, 0.30 mmol) in DMF (5 mL) was stirred at room temperature for 40 hours. Then, _H2O (5 mL) was added to the reaction and stirred for another 1 h. The mixture was extracted with EtOAc (2 x 25 mL). The combined organic phases were dried over _Na2SO4 , filtered and concentrated _under reduced pressure to give crude product. Then, the residue was dissolved in 30% methanolic ammonia (20 mL) and stirred at room temperature for 12 hours. After removal of all volatiles, the residue was purified by silica gel column chromatography (gradient DCM/MeOH, 20:1, v/v; 15:1, v/v; 10:1, v/v) to give a colorless oil 48b (80 mg, 67%) in the form of a compound. ¹ H NMR (300MHz, CDCl ₃ ): δ10.89(s, 1H, NHCO), 7.30(d, J=1.1Hz, 1H, H-6), 4.71-4.28(m, 3H, H-3', H-1'a),4.21-3.93(m,7H,H-1'b,H-2',2x CH ₂ CH ₃ ,PCH ₂ a),3.87-3.80(m,1H,PCH ₂ b), 1.38-1.32 (m, 6H, 2xCH ₂ CH ₃ ); ¹³ C NMR (75MHz, CDCl ₃ ): δ159.2 (C-4), 154.0 (C-2), 152.2 (C-7a), 130.9 (C -6),115.5(C-5),99.5(C-4a),86.6(CN),82.4(d, ¹ J _C,P ＝173.5Hz,C-3'),79.1(dd, ² J _{C, F} ＝19.2Hz, ³ J _C,P ＝10.4Hz,C-2'),64.8(d, ¹ J _C,P ＝167.2Hz,CH ₂ P),63.0,62.9(CH ₂ CH ₃ ),45.2( d, ³ J _C,F = 8.2Hz, C-1'), 16.8, 16.7 (CH ₂ CH ₃ ); ³¹ P NMR (121 MHz, CDCl ₃ ): δ20.7; HRMS for C ₁₅ H ₂₁ FN ₅ O ₅ P[M+H] ⁺ calculated: 402.1336, found: 402.1329.

Example 59: (R)-2-Amino-6-(4-methoxyphenylthio)-9-[2-(phosphonomethoxy)-3-fluoropropyl]purine (33a)

Bromotrimethylsilane (0.43mL, 3.20mmol) was added dropwise to diethylphosphonate 32a (200mg, 0.40mmol) and 2,6-lutidine (0.74mL, 6.40mmol) at 0°C ) in anhydrous acetonitrile (10 mL). After the addition was complete, the mixture was slowly warmed to room temperature and left in the dark for 12 hours. The reaction was quenched with 0.1M TEAB, then concentrated under reduced pressure. Column chromatography on silica gel (gradient: acetone/Et ₃ N/H ₂ O, 6:1:1, v/v/v), followed by RP-HPLC (linear gradient, 2-98% CH ₃ CN in 0.05M TEAB ) to afford the desired triethylammonium phosphonate salt 33a (120 mg, 70%) as a white foam. ¹ H NMR (300MHz, D ₂ O): δ7.93 (s, 1H, H-8), 7.19 (d, J = 8.8Hz, 2H, ArH), 6.73-6.70 (m, 2H, ArH), 4.60 -4.21(m,2H,H-3'),4.18-4.08(m,2H,H-1'),3.89-3.81(m,1H,H-2'),3.61(s,3H,OCH ₃ ) , 3.59-3.41 (m, 2H, PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ161.1 (C-2), 160.0 (Ar-C), 159.3 (C-6), 150.1 (C -4), 142.8(C-8), 136.8(Ar-C), 123.0(C-5), 116.8(Ar-C), 114.8(Ar-C), 82.1(d, ¹ J _{C, P} = 168.0 Hz,C-3'),77.4(dd, ² J _C,F ＝18.9Hz, ³ J _C,P ＝11.2Hz,C-2'),66.9(d, ¹ J _C,P ＝154.8Hz,CH ₂ P), 55.3 (OCH ₃ ), 42.7 (d, ³ J _{C, F} = 7.1 Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ14.1; HRMS for C ₁₆ H ₁₉ FN ₅ O ₅ PS [MH] ^- Calculated: 442.0756, Found: 442.0752.

Example 60: (S)-2-Amino-6-(4-methoxyphenylthio)-9-[2-(phosphonomethoxy)-3-fluoropropyl]purine (33b)

According to the preparation procedure for 33a, from compound 32b (150 mg, 0.30 mmol), bromotrimethylsilane (0.32 mL, 2.40 mmol) and 2,6-lutidine (0.56 mL, 4.80 mmol) in anhydrous acetonitrile (10 mL), compound 33b (86 mg, 65%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/ _Et3N / _H2O , 6:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ7.95 (s, 1H, H-8), 7.22 (d, J=8.4Hz, 2H, ArH), 6.82-6.65 (m, 2H, ArH), 4.63 -4.24(m,2H,H-3'),4.20-4.10(m,2H,H-1'),3.93-3.85(m,1H,H-2'),3.64(s,3H,OCH ₃ ) , 3.61-3.45 (m, 2H, PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ161.1 (C-2), 160.0 (Ar-C), 159.3 (C-6), 150.1 (C -4), 142.8(C-8), 136.8(Ar-C), 123.0(C-5), 116.8(Ar-C), 114.8(Ar-C), 82.1(d, ¹ J _{C, P} = 168.1 Hz,C-3'),77.5(dd, ² J _C,F ＝18.9Hz, ³ J _C,P ＝11.1Hz,C-2'),66.7(d, ¹ J _C,P ＝155.5Hz,CH ₂ P), 55.3 (OCH ₃ ), 42.8 (d, ³ J _{C, F} = 7.1 Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ14.3; HRMS for C ₁₆ H ₁₉ FN ₅ O ₅ PS [MH] ^- Calculated: 442.0756, Found: 442.0734.

Example 61: (R)-2-Amino-3,4-dihydro-7-(2-phosphonomethoxy-3-fluoropropyl)-7H-pyrrolo[2,3-d]pyrimidine- 4-keto (40a)

From compound 38a (100 mg, 0.26 mmol), bromotrimethylsilane (0.28 mL, 2.12 mmol) and 2,6-lutidine (0.50 mL, 4.24 mmol) in anhydrous acetonitrile according to the procedure for the preparation of 33a (10 mL), compound 40a (59 mg, 70%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/ _Et3N / _H2O , 4:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ6.65(d, J=3.7Hz, 1H, H-6), 6.17(d, J=3.6Hz, 1H, H-5), 4.50-4.04(m ,2H,H-3'),4.95-3.93(m,2H,H-1'),3.83-3.70(m,1H,H-2'),3.41(d,J＝9.2Hz,2H,PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ160.8(C-4), 152.0(C-2), 150.3(C-7a), 123.1(C-6), 100.9(C-5), 99.5(C-4a),82.3(d, ¹ J _C,P ＝167.3Hz,C-3'),78.0(dd, ² J _C,F ＝18.4Hz, ³ J _C,P ＝10.7Hz,C- 2'), 67.6(d, ¹ J _{C, P} ＝151.9Hz, CH ₂ P), 43.4(d, ³ J _{C, F} ＝7.3Hz, C-1'); ³¹ P NMR (121MHz, D ₂ O ): δ 12.3; HRMS for C ₁₀ H ₁₄ FN ₄ O ₅ P [MH] ^- calcd: 319.0612, found: 319.0611.

Example 62: (S)-2-Amino-3,4-dihydro-7-(2-phosphonomethoxyl-3-fluoropropyl)-7H-pyrrolo[2,3-d]pyrimidine -4-keto (40b)

According to the procedure for the preparation of 33a, from compound 38b (50 mg, 0.13 mmol), bromotrimethylsilane (0.14 mL, 1.06 mmol) and 2,6-lutidine (0.25 mL, 2.12 mmol) in anhydrous acetonitrile (5 mL), compound 40b (30 mg, 70%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/ _Et3N / _H2O , 4:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ6.73(d, J=3.5Hz, 1H, H-6), 6.25(d, J=3.5Hz, 1H, H-5), 4.56-4.11(m ,2H,H-3'),4.09-3.98(m,2H,H-1'),3.90-3.78(m,1H,H-2'),3.42(d,J＝9.2Hz,2H,PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ166.0 (C-4), 156.5 (C-2), 151.1 (C-7a), 122.3 (C-6), 100.6 (C-4a, C -5),82.4(d, ¹ J _C,P ＝167.0Hz,C-3'),78.0(dd, ² J _C,F ＝18.2Hz, ³ J _C,P ＝10.4Hz,C-2') ,68.1(d, ¹ J _{C, P} ＝150.0Hz, CH ₂ P), 43.2(d, ³ J _{C, F} ＝7.2Hz, C-1'); ³¹ P NMR (121MHz, D ₂ O): δ12 .6; HRMS calcd for _C10H14FN4O5P [MH] ^- _319.0612 , found _{: 319.0598} .

Example 63: (R)-2-Amino-5-fluoro-3,4-dihydro-7-{2-phosphonomethoxy-3-fluoropropyl}-7H-pyrrolo[2,3- d] pyrimidin-4-one (41a)

From compound 39a (20 mg, 0.05 mmol), bromotrimethylsilane (0.05 mL, 0.40 mmol) and 2,6-lutidine (0.09 mL, 0.81 mmol) in anhydrous acetonitrile according to the procedure for the preparation of 33a (5 mL), compound 41a (9 mg, 50%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/ _Et3N / _H2O , 4:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ6.56 (d, J=2.1Hz, 1H, H-6), 4.59-4.16 (m, 2H, H-3'), 4.00-3.98 (m, 2H , H-1'), 3.90-3.81 (m, 1H, H-2'), 3.49 (d, J=9.1Hz, 2H, PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ159.5 (d, ³ J _C,F ＝2.8Hz,C-4),152.3(C-2),146.0(d, ³ J _C,F ＝3.0Hz,C-7a),144.6(d, ¹ J _{C, F} ＝246.3Hz, C-5), 105.1(d, ¹ J _{C, F} ＝26.6Hz, C-6), 90.0(d, ¹ J _{C, F} ＝14.4Hz, C-4a), 82.4(d, ¹ J _C,P ＝167.2Hz,C-3'),78.1(dd, ² J _C,F ＝18.3Hz, ³ J _C,P ＝10.4Hz,C-2'),67.2(d, ¹ J _{C , P} = 153.2Hz, CH ₂ P), 43.2 (d, ³ J _{C, F} = 7.4 Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ13.8; HRMS for C ₁₀ H _13F2N4O5P [MH] - _calcd : _{337.0519 ,} found: 337.0503.

Example 64: (S)-2-Amino-5-fluoro-3,4-dihydro-7-{2-phosphonomethoxy-3-fluoropropyl}-7H-pyrrolo[2,3- d] pyrimidin-4-one (41b)

According to the procedure for the preparation of 33a, from compound 39b (20 mg, 0.05 mmol), bromotrimethylsilane (0.05 mL, 0.40 mmol) and 2,6-lutidine (0.09 mL, 0.81 mmol) in anhydrous acetonitrile (5 mL), compound 41b (10 mg, 60%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/ _Et3N / _H2O , 4:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ6.52 (d, J=2.2Hz, 1H, H-6), 4.57-4.09 (m, 2H, H-3'), 4.07-3.92 (m, 2H , H-1'), 3.89-3.77 (m, 1H, H-2'), 3.43 (d, J=9.1Hz, 2H, PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ167.1 (C-4),159.1(C-2),147.4(C-7a),144.6(d, ¹ J _C, F ＝244.3Hz,C-5),103.5(d, ² J _C,F ＝27.2Hz ,C-6),91.2(d, ² J _C,F ＝14.4Hz,C-4a),82.4(d, ¹ J _C,P ＝166.9Hz,C-3'),77.9(dd, ² J _{C ,F} ＝18.2Hz, ³ J _C,P ＝10.3Hz,C-2'),68.1(d, ¹ J _C,P ＝150.1Hz,CH ₂ P),42.7(d, ³ J _C,F ＝7.2 Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ 12.7; HRMS for C ₁₀ H ₁₃ F ₂ N ₄ O ₅ P [MH] - calcd: 337.0519, found: 337.0522.

Example 65: (R)-2-Amino-5-cyano-3,4-dihydro-7-{2-phosphonomethoxy-3-fluoropropyl}-7H-pyrrolo[2,3 -d]pyrimidin-4-one (49a)

From compound 48a (50 mg, 0.13 mmol), bromotrimethylsilane (0.13 mL, 1.00 mmol) and 2,6-lutidine (0.23 mL, 2.00 mmol) in anhydrous acetonitrile according to the procedure for the preparation of 33a (5 mL), compound 49a (30 mg, 70%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/ _Et3N / _H2O , 5:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ7.51(s, 1H, H-6), 4.60-4.21(m, 2H, H-3'), 4.10-4.08(m, 2H, H-1' ), 3.90-3.83 (m, 1H, H-2'), 3.44 (d, J=9.1Hz, 2H, PCH ₂ ); ¹³ C NMR (75MHz, D ₂ O): δ162.0 (C-4) ,155.6(C-2),151.1(C-7a),132.6(C-6),116.2(C-5),99.3(C-4a),84.3(CN),82.2(d, ¹ J _C,P ＝167.1Hz,C-3'),77.3(dd, ² J _C,F ＝18.6Hz, ³ J _C,P ＝10.5Hz,C-2'),68.0(d, ¹ J _C,P ＝149.9Hz , CH ₂ P), 44.1 (d, ³ J _{C, F} = 7.0 Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ12.5; HRMS for C ₁₁ H ₁₃ FN ₅ O ₅ P[MH] ^- Calculated: 344.0565, Found: 344.0573.

Example 66: (S)-2-Amino-5-cyano-3,4-dihydro-7-{2-phosphonomethoxy-3-fluoropropyl}-7H-pyrrolo[2,3 -d] pyrimidin-4-one (49b)

From compound 48b (80 mg, 0.20 mmol), bromotrimethylsilane (0.21 mL, 1.60 mmol) and 2,6-lutidine (0.37 mL, 3.20 mmol) in anhydrous acetonitrile according to the procedure for the preparation of 33a (5 mL), compound 49b (51 mg, 75%) was obtained as a white foam. The crude residue was purified by silica gel column chromatography (gradient acetone/ _Et3N / _H2O , 5:1:1, v/v/v). ¹ H NMR (300MHz, D ₂ O): δ7.40 (d, J=1.1Hz, 1H, H-6), 4.70-4.20 (m, 2H, H-3'), 4.08-3.93 (m, 2H ,H-1'),3.90-3.78(m,1H,H-2'),3.58-3.42(m,2H,PCH ₂ ); ¹³ C NMR(75MHz,D ₂ O): δ159.0(C- 4), 153.3(C-2), 150.7(C-7a), 132.7(C-6), 115.7(C-5), 98.7(C-4a), 84.6(CN), 82.2(d, ¹ J _{C ,P} ＝167.7Hz,C-3'),77.7(dd, ² J _C,F ＝18.5Hz, ³ J _C,P ＝11.3Hz,C-2'),66.7(d, ¹ J _C,P ＝ 155.2Hz, CH ₂ P), 44.3 (d, ³ J _{C, F} = 7.6Hz, C-1'); ³¹ P NMR (121 MHz, D ₂ O): δ14.3; HRMS for C ₁₁ H ₁₃ FN ₅ O ₅ P[MH] ^- Calculated: 344.0565, Found: 344.0557.

Example 67: Dipentyl (((((R)-1-(2-amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d]pyrimidin-7-yl )-3-fluoropropan-2-yl)oxy)methyl)(phenoxy)phosphoryl)-L-aspartate (50)

Compound 40a (40mg, 0.09mmol, Et ₃ N salt) was mixed with L-aspartic acid pentamethylenediester HCl salt (Maiti, M.; Maiti, M.; Rozenski, J.; De Jonghe, S.; Herdewijn, P.Aspartic acid based nucleotide phosphoramidate prodrugs as potent inhibitors of hepatitis C virus replication.Org.Biomol.Chem.2015,13,5158-5174) (50mg, 0.16mmol) and phenol (40mg, 0.42mmol) in anhydrous pyridine (53mL) mix. Then, Et ₃ N (0.13 mL, 0.95 mmol) was added, and the mixture was stirred at 60° C. under nitrogen atmosphere for 15-20 minutes. In a separate flask, 2,2'-dithiobipyridine (150 mg, 0.66 mmol) was mixed with a solution of PPh ₃ (180 mg, 0.66 mmol) in anhydrous pyridine (2 mL), and the resulting mixture was stirred for 10-15 Minutes, a clear light yellow solution was obtained. Then, this solution was added to the above solution, and the combined mixture was stirred at 60° C. for 12 hours. Then, the mixture was concentrated under reduced pressure to give a residue, which was redissolved in EtOAc (50 mL). The solution was washed with saturated aqueous NaHCO ₃ (25 mL) and brine (25 mL), the organic layer was separated, dried over Na ₂ SO ₄ , filtered, and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography (gradient DCM/MeOH, 30:1, v/v; 20:1, v/v) followed by RP-HPLC (linear gradient, 5-95% _CH3CN in water) , Compound 50 (60 mg, 40%) was obtained in the form of white powder. ¹ H NMR (300MHz, CD ₃ CN): δ10.08(s, 1H, NHCO), 7.37-7.08(m, 5H, ArH), 6.72-6.69(m, 1H, H-6), 6.40-6.38( m,1H,H-5),5.80,5.78(s,2H,NH ₂ ),4.70-4.25(m,4H,H-3',NHPO,H-α-Asp),4.16-3.89(m,9H ,H-1',H-2',2x OCH ₂ (CH ₂ ) ₃ CH ₃ ,PCH ₂ ),2.84-2.57(m,2H,H-β-Asp),1.58-1.52(m,4H,2x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ),1.32-1.24(m,8H,2x O(CH 2 ) ₂ (CH _{2 ) 2} CH ₃ ),0.91-0.84(m,6H,2xO(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ172.9, 172.8, 172.7(CO-α), 171.6(CO-β), 160.5(C-4), 153.5, 153.4(C-2) ,152.0,151.9(C-7a),130.7(Ar-C),125.9(Ar-C),122.4(C-6),121.9,121.8(Ar-C),102.7(C-5),101.7(C -4a),83.6(d, ¹ J _C,F ＝170.3Hz,C-3'),83.5(d, ¹ J _C,F ＝170.0Hz,C-3'),80.7,80.5,80.4,80.3, 80.1(C-2'),66.8(d, ¹ J _C,P ＝156.2Hz, CH ₂ P),66.6(d, ¹ J _C,P ＝154.2Hz, CH ₂ P),66.6,65.9,65.8( OCH ₂ (CH ₂ ) ₃ CH ₃ ), 51.7, 51.6 (C-α-Asp), 45.1, 45.0, 44.9 (C-1'), 39.9 (d, ³ J _{C, P} = 3.9 Hz, C-β -Asp), 39.7(d, ³ J _{C, P} ＝3.9Hz, C-β-Asp), 29.1, 29.0, 28.8, 28.7(OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.1, 23.0 (O (CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3 (O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121 MHz, CD ₃ CN): δ 23.0, 22.2; HRMS for Calcd. for _C30H43FN5O8P [M+H] ⁺ : 652.2905, _{found : 652.2923} .

Example 68: Tetrapentyl 2,2'-((((((R)-1-(2-amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d ]pyrimidin-7-yl)-3-fluoropropan-2-yl)oxy)methyl)phosphoryl)bis(azanediyl))(2S,2'S)-hydrogen succinate (51)

Compound 40a (15 mg, 0.04 mmol, Et ₃ N salt) was mixed with L-aspartic acid pentamethylene glycol ester HCl salt (Maiti, M.; Maiti, M.; Rozenski, J.; De Jonghe, S.; Herdewijn, P. Aspartic acid based nucleotide phosphoramidate prodrugs as potent inhibitors of hepatitis C virus replication. Org. Biomol. Chem. 2015, 13, 5158-5174) (44 mg, 0.14 mmol) were mixed with anhydrous pyridine (3 mL). Then, Et ₃ N (0.04 mL, 0.40 mmol) was added, and the mixture was stirred at 60° C. under nitrogen atmosphere for 15-20 minutes. In a separate flask, 2,2'-dithiobipyridine (55 mg, 0.25 mmol) was mixed with a solution of PPh ₃ (65 mg, 0.25 mmol) in anhydrous pyridine (2 mL), and the resulting mixture was stirred for 10-15 Minutes, a clear light yellow solution was obtained. Then, this solution was added to the above solution, and the combined mixture was stirred at 60° C. for 12 hours. Then, the mixture was concentrated under reduced pressure to give a residue, which was redissolved in EtOAc (50 mL). The solution was washed with saturated aqueous NaHCO ₃ (25 mL) and brine (25 mL), the organic layer was separated, dried over Na ₂ SO ₄ , filtered, and concentrated under reduced pressure. The crude residue was purified by silica gel chromatography (gradient DCM/MeOH, 30:1, v/v; 20:1, v/v) followed by RP-HPLC (linear gradient, 5-95% CHCN in water), Compound 51 (5 mg, 20%) was obtained in the form of white powder. ¹ H NMR (300MHz, CD ₃ CN): δ9.87(s, 1H, NHCO), 6.63(d, J=3.5Hz, 1H, H-6), 6.32(d, J=3.5Hz, 1H, H -5),6.06(s,2H,NH ₂ ),4.68,3.74(m,19H,H-3',2x NHPO,2x H-α-Asp,H-1',H-2',4x OCH ₂ (CH ₂ ) ₃ CH ₃ , PCH ₂ ), 2.89-2.73(m, 4H, 2x H-β-Asp), 1.61-1.53(m, 8H, 4x OCH ₂ CH ₂ (CH ₂ ) ₂ CH ₃ ), 1.33-1.24 (m, 16H, 4x O(CH ₂ ) ₂ (CH ₂ ) ₂ CH ₃ ), 0.91-0.84 (m, 12H, 4x O(CH ₂ ) ₄ CH ₃ ); ¹³ C NMR (75MHz, CD ₃ CN): δ173.3, 173.2 (CO-α), 171.9, 171.8 (CO-β), 160.0 (C-4), 153.7 (C-2), 151.6 (C-7a), 122.1 (C-6), 102.8(C-5),101.8(C-4a),83.1(d, ¹ J _C,F ＝170.2Hz,C-3'),80.13(dd, ² J _C,F ＝18.7Hz, ³ J _{C, P} ＝11.5Hz, C-2'), 68.1(d, ¹ J _{C, P} ＝136.9Hz, CH ₂ P), 66.6, 66.5, 65.8(OCH ₂ (CH ₂ ) ₃ CH ₃ ), 51.1, 50.5( C-α-Asp), 44.86(d, J＝8.1Hz, C-1'), 40.0, 39.9, 39.8(d, ³ J _{C, P} ＝3.9Hz, C-β-Asp), 29.1, 29.0, 28.8(OCH ₂ (CH ₂ ) ₂ CH ₂ CH ₃ ), 23.1, 23.0(O(CH ₂ ) ₃ CH ₂ CH ₃ ), 14.3(O(CH ₂ ) ₄ CH ₃ ); ³¹ P NMR (121MHz, CD ₃ CN): δ 21.5; HRMS for C ₃₈ H ₆₄ FN ₆ O ₁₁ P [MH] ^- calcd: 829.4282, found: 829.4298.

Example 69: HBV Antiviral Assay in HepG2 2.2.15 Cells

Primary anti-HBV assays were performed as previously described (Korba, BF and Milman, G. A cell culture assay for compound which inhibit hepatitis B virus replication. Antiviral Res. 1991, 15, 217-228; and Korba, BF and Gerin, JL. Use of a standardized cell culture assay to assess activities of nucleotide analogs again hepatitis B virus replication. Antiviral Res. 1992, 19, 55-70), which was modified to use real-time qPCR (TaqMan) to measure cellularity associated with virions released from HepG2 2.2.15 cells External HBV DNA copy number. The HepG2 2.2.15 cell line is a stable human hepatoblastoma cell line that contains two copies of the HBV wild-type strain aywl genome and constitutively produces high levels of HBV. This cell line can be used to identify and characterize antiviral compounds that block any late steps of viral replication such as transcription, translation, pregenome encapsidation, reverse transcription, virion assembly and release.

Briefly, Dahl supplemented with 2% FBS, 380 μg/mL G418, 2.0 mM L-glutamine, 100 units/mL penicillin, 100 μg/mL streptomycin and 0.1 mM non-essential amino acids HepG2 2.2.15 cells were plated in 96-well microtiter plates at 1.5 x ¹⁰⁴ cells/well in Burke's modified Eagle's medium. Only the inner wells were used to reduce the "edge effect" observed during cell culture; the outer wells were filled with complete medium to help minimize sample evaporation. After 16–24 h, confluent monolayers of HepG2 2.2.15 cells were washed and the medium was replaced in triplicate with complete medium containing different concentrations of test compounds. Lamivudine (3Tc) and Entecavir were used as positive controls, while medium alone was added to the cells as a negative control (virus control, VC). After three days, the medium was replaced with fresh medium containing an appropriate dilution of the test compound. Six days after the initial dosing of test compounds, cell culture supernatants were collected, treated with pronase, and then used in real-time quantitative TaqMan qPCR assays. PCR-amplified HBV DNA is detected in real time by monitoring the increase in fluorescent signal generated by the exonucleic degradation of quenched fluorescent probe molecules that hybridize to the amplified HBV DNA. For each PCR amplification, a standard curve was simultaneously generated using dilutions of purified HBV DNA. Antiviral activity (determined EC ₅₀ and EC ₉₀ values) was calculated from the reduction in HBV DNA levels. Then, the tetrazolium dye (MTS; 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy-methoxyphenyl)-2-(4-sulfophenyl) -2H-tetrazole; Reagent, Promega) uptake assay was used to measure cell viability, which was used to calculate toxicity ( _CC50 ). Selectivity index (SI ₅₀ ) was calculated as CC ₅₀ /IC ₅₀ . Data are shown in Table 1.

^a Effective concentration (expressed in [mu]M) required to reduce HBV-induced cytopathy by 50%.

^b Effective concentration (expressed in [mu]M) required to reduce HBV-induced cytopathy by 90%.

^c Cytotoxic concentration (expressed in [mu]M) required to reduce cell growth by 50%.

Table 1

Example 70: Antiviral activity against HIV-1X4 strain NL4.3 and HIV-1R5 strain BaL

TZM-bl cells (Montefiori, D.C. Methods Mol. Biol. 2009, 485, 395-405) were placed in DMEM containing 10% fetal bovine serum (FBS) and 10 mM HEPES (Dulbecco's Modified I Gehl's medium; Life Technologies, Waltham, MA, USA) were inoculated in transparent 96-well plates. Subsequently, compound was added and the cell/compound mixture was incubated at 37°C. After 30 minutes, virus was added at 100 pg p-24 per well. After 48 hours of incubation, assay plates were analyzed. For analysis, steadylite plus substrate solution (PerkinElmer, Waltham, MA, USA) was added to the assay plate. After a 10 min incubation period in the dark, lysed cell suspensions were analyzed for luminescent signal in white 96-well plates on a SpectraMax L luminescent microplate reader (Molecular Devices, Sunnyvale, CA, USA). HIV-1 Tat protein expression induced luciferase activity was measured as an assessment of the amount of HIV replication. Data are shown in Table 2.

^a Effective concentration (expressed in [mu]M) required to reduce HIV-induced cytopathy by 50%.

^b Cytotoxic concentration (expressed in [mu]M) required to reduce cell growth by 50%.

Table 2

Example 71: Antiviral activity against varicella zoster virus and human cytomegalovirus

Compounds of the invention were evaluated against varicella-zoster virus (VZV) strain Oka and thymidine kinase-deficient (TK ⁻ ) VZV strain 07-1 and human cytomegalovirus (HCMV) strains AD-169 and Davis. The antiviral assay is based on the inhibition of virus-induced cytopathy or plaque formation in human embryonic lung (HEL) fibroblasts. Confluent cell cultures in microtiter 96-well plates were inoculated with 100 CCID ₅₀ of HCMV (1 CCID ₅₀ is the virus dose to infect 50% of the cell culture) or with 20 plaque forming units (PFU) (VZV). After an adsorption period of 1-2 hours, residual virus was removed and cell cultures were incubated in the presence of different concentrations of test compounds. Viral cytopathy (HCMV) or plaque formation (VZV) was recorded once it reached completion in control virus-infected cell cultures not treated with test compound. Antiviral activity is expressed as _EC50 or concentration (expressed in micromolar) required to reduce virus-induced cytopathic or viral plaque formation by 50%. Cell growth inhibition measurements are based on the inhibition of cell growth. HEL cells were seeded into 96-well microtiter plates at a rate of 5 × ¹⁰³ cells/well and allowed to proliferate for 24 h. Then, medium containing different concentrations of test compounds was added. After 3 days of incubation at 37°C, cell numbers were determined with a Coulter counter. Cytostatic concentrations (expressed in micromolar) were calculated as _CC50 , or the concentration of compound required for a 50% reduction in cell proliferation relative to the number of cells in untreated controls. _CC50 values were estimated from a graphical plot of cell number (percentage of control) as a function of test compound concentration. Alternatively, the cytotoxicity of test compounds is expressed as the minimum cytotoxic concentration (MCC), or the concentration of the compound that causes a microscopically detectable change in cell morphology. Ganciclovir and cidofovir were included as positive controls for HCMV testing, while acyclovir and bromfuridine were used as reference drugs in the VZV assay. Data are shown in Table 3.

^a _EC50 = effective concentration (expressed in [mu]M) required to reduce virus-induced cytopathy by 50%.

^b MCC = minimum concentration (expressed in [mu]M) required to cause a microscopically detectable change in cell morphology.

^c _CC50 = Cytotoxic concentration (expressed in [mu]M) required to reduce cell growth by 50%.

^d ND = not determined

table 3

references

1. Pertusati, F.; Hinsinger, K.; Flynn, A.S.; Powell, N.; .

2. Pomeisl, K.; Pohl, R.; Holy, A.; Votruba, I. Collect. Czech. Chem. Commun. 2005, 70, 1465-1481.

3. Jindrich, J.; Holy, A.; Dvorakova, H. Collect. Czech. Chem. Commun. 1993, 58, 1645-1667.

4. Baszczynski, O.; Hockova, D.; Janeba, Z.; Holy, A.; Jansa, P.; Dracinsky, M.; Keough, D.T.; , 81-89.

Claims (16)

1. A compound of formula I: in -B is any natural or modified nucleobase -R ¹ has the general formula II in -R ³ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ -cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) A group consisting of alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl; -R ⁴ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl, alkoxyalkyl, X-COOR ⁵ , The group consisting of XO(C=O)-R ⁵ ; wherein X is aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl or C ₃ -C ₈ -cycloalkyl, and wherein said aryl , heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, C ₃ -C ₈ -cycloalkyl optionally contain one or more independently selected from Functional groups, atoms or radicals of the group consisting of halogen, haloalkyl, cyano, C ₁ -C ₇ alkoxy; and wherein R ⁵ is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) group consisting of C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl; ^-R is O-Ar, where Ar is a fused bicyclic aryl moiety or a monocyclic aryl moiety, wherein either aryl moiety is carbocyclic or heterocyclic and is optionally replaced by halogen, _C1 - _C6 alkane Base, C ₁ -C ₆ alkoxy substitution; or ^R2 has the general formula II Wherein R ¹ and R ² can be the same or different; And/or its pharmaceutically acceptable addition salt and/or its stereoisomer and/or its solvate. 2. The compound according to claim 1, wherein B is selected from the group of adenine, thymine, cytosine and guanine. 3. The compound according to claim 1 or 2, wherein R ² is O-Ph. 4. The compound according to any one of claims 1 to 3, wherein ^R3 is selected from _C1 - _C10 alkyl. 5. The compound according to any one of statements 1 to 4, wherein R ⁴ is X-COOR ⁵ and wherein X is aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenes C ₂ -C ₁₀ alkynyl or C ₃ -C ₈ -cycloalkyl, and wherein said aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ - C ₁₀ alkynyl, _{C 3} -C _{8 -cycloalkyl} optionally contain one or more functional groups, atoms or and wherein R ^is selected from aryl, heteroaryl, C ₁ -C ₁₀ alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₈ cycloalkyl-alkyl, aryl (C ₁ -C ₆ ) alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, hydroxy C ₁ -C ₁₀ alkyl, halogenated C ₁ -C ₁₀ alkyl and alkoxyalkyl Group. 6. The compound according to any one of claims 1 to 5, wherein X is C _{1 -C 10} alkyl and R ⁵ is C _{1 -C 10} alkyl. 7. The compound according to any one of claims 1 to 6, wherein R ² is O-Ph and wherein R ¹ is 8. One selected from: (S)-1-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}thymine ; (R)-1-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}thymine; (S)-9 -{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}adenine; (R)-9-{3-fluoro- 2-[Phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}adenine; (S)-1-{3-fluoro-2-[phenyloxy Base-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}cytosine; (R)-1-{3-fluoro-2-[phenyloxy-bis(pentyl) -L-Aspartyl)phosphoryl]methoxy]propyl}cytosine; (S)-9-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartate) Acyl)phosphoryl]methoxy]propyl}guanine; (R)-9-{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methyl Oxy]propyl}guanine; (S)-O ² -{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl }cytosine; (R)-O ² -{3-fluoro-2-[phenyloxy-bis(pentyl-L-aspartyl)phosphoryl]methoxy]propyl}cytosine; two Amyl (((((R)-1-(2-amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-fluoro Propan-2-yl)oxy)methyl)(phenoxy)phosphoryl)-L-aspartate; tetrapentyl 2,2'-((((((R)-1-(2 -Amino-4-oxo-3,4-dihydro-7H-pyrrolo[2,3-d]pyrimidin-7-yl)-3-fluoropropan-2-yl)oxy)methyl)phosphoryl ) Compounds of the group consisting of bis(azanediyl))(2S,2'S)-hydrogen succinate. 9. A compound according to any one of claims 1 to 8 for use as a medicament. 10. A compound according to any one of claims 1 to 8, for use as a medicament for the prophylaxis or treatment of viral infections in animals, mammals or humans. 11. The compound according to claim 10, wherein the viral infection is caused by hepatitis B virus (HBV), human immunodeficiency virus (HIV), varicella zoster virus (VZV), cytomegalovirus (CMV), Vaccinia virus (VV), herpes simplex virus (HSV), BK virus, Epstein-Barr virus (EBV), papillomavirus, monkeypox virus, vaccinia virus, hepatitis C virus (HCV), respiratory syncytial virus (RSV), dengue, influenza, adenovirus, parainfluenza and/or rhinovirus infection. 12. A compound according to any one of claims 1 to 8 for use as a medicament for the prevention or treatment of a proliferative disease such as cancer in animals, mammals or humans. 13. A pharmaceutical composition comprising a therapeutically effective amount of a compound according to any one of claims 1 to 8 and one or more pharmaceutically acceptable excipients. 14. The pharmaceutical composition according to claim 13, further comprising one or more bioactive drugs selected from the group consisting of antiviral drugs and/or antiproliferative drugs. 15. A method of preventing or treating viral infection in animals, mammals or humans, comprising administering a therapeutically effective amount of a compound according to any one of claims 1 to 8, optionally in combination with one or more Pharmaceutically acceptable excipients. 16. A method of preventing or treating proliferative diseases in animals, mammals or humans, comprising administering a therapeutically effective amount of a compound according to any one of claims 1 to 8, optionally in combination with one or more a pharmaceutically acceptable excipient.